Handling click events on a drawable within an Edit

2019-01-01 04:40发布

I have added an image right of the text in an EditText widget, using the following XML:

<EditText
  android:id="@+id/txtsearch"
  ...
  android:layout_gravity="center_vertical"
  android:background="@layout/shape"
  android:hint="Enter place,city,state"
  android:drawableRight="@drawable/cross" />

But I want to clear the EditText when the embedded image is clicked. How can I do this?

30条回答
梦该遗忘
2楼-- · 2019-01-01 04:58

Simply copy paste the following code and it does the trick.

editMsg.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            final int DRAWABLE_LEFT = 0;
            final int DRAWABLE_TOP = 1;
            final int DRAWABLE_RIGHT = 2;
            final int DRAWABLE_BOTTOM = 3;

            if(event.getAction() == MotionEvent.ACTION_UP) {
                if(event.getRawX() >= (editMsg.getRight() - editMsg.getCompoundDrawables()[DRAWABLE_RIGHT].getBounds().width())) {
                    // your action here

                    Toast.makeText(ChatActivity.this, "Message Sent", Toast.LENGTH_SHORT).show();
                    return true;
                }
            }
            return false;
        }
    });
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栀子花@的思念
3楼-- · 2019-01-01 04:58

for left drawable click listener

txt.setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            final int DRAWABLE_LEFT = 0;

            if (event.getAction() == MotionEvent.ACTION_UP) {
                if (event.getRawX() <= (txt
                        .getCompoundDrawables()[DRAWABLE_LEFT].getBounds().width() +
                        txt.getPaddingLeft() +
                        txt.getLeft())) {

                          //TODO do code here
                    }
                    return true;
                }
            }
            return false;
        }
    });
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孤独总比滥情好
4楼-- · 2019-01-01 04:59

Sharing my generalized solution for handling TextView compound drawable click and touch events.

First we need a touch event handler:

/**
 * Handles compound drawable touch events.
 * Will intercept every event that happened inside (calculated) compound drawable bounds, extended by fuzz.
 * @see TextView#getCompoundDrawables()
 * @see TextView#setCompoundDrawablesRelativeWithIntrinsicBounds(int, int, int, int)
 */
public abstract class CompoundDrawableTouchListener implements View.OnTouchListener {

    private final String LOG_TAG = "CmpDrawableTouch";

    private final int fuzz;

    public static final int LEFT = 0;
    public static final int TOP = 1;
    public static final int RIGHT = 2;
    public static final int BOTTOM = 3;
    private static final int[] DRAWABLE_INDEXES = {LEFT, TOP, RIGHT, BOTTOM};

    /**
     * Default constructor
     */
    public CompoundDrawableTouchListener() {
        this(0);
    }

    /**
     * Constructor with fuzz
     * @param fuzz desired fuzz in px
     */
    public CompoundDrawableTouchListener(int fuzz) {
        this.fuzz = fuzz;
    }

    @Override
    public boolean onTouch(View view, MotionEvent event) {
        if (!(view instanceof TextView)) {
            Log.e(LOG_TAG, "attached view is not instance of TextView");
            return false;
        }

        TextView textView = (TextView) view;
        Drawable[] drawables = textView.getCompoundDrawables();
        int x = (int) event.getX();
        int y = (int) event.getY();

        for (int i : DRAWABLE_INDEXES) {
            if (drawables[i] == null) continue;
            Rect bounds = getRelativeBounds(i, drawables[i], textView);
            Rect fuzzedBounds = addFuzz(bounds);

            if (fuzzedBounds.contains(x, y)) {
                MotionEvent relativeEvent = MotionEvent.obtain(
                    event.getDownTime(),
                    event.getEventTime(),
                    event.getAction(),
                    event.getX() - bounds.left,
                    event.getY() - bounds.top,
                    event.getMetaState());
                return onDrawableTouch(view, i, bounds, relativeEvent);
            }
        }

        return false;
    }

    /**
     * Calculates compound drawable bounds relative to wrapping view
     * @param index compound drawable index
     * @param drawable the drawable
     * @param view wrapping view
     * @return {@link Rect} with relative bounds
     */
    private Rect getRelativeBounds(int index, @NonNull Drawable drawable, View view) {
        Rect drawableBounds = drawable.getBounds();
        Rect bounds = new Rect();

        switch (index) {
            case LEFT:
                bounds.offsetTo(view.getPaddingLeft(),
                    view.getHeight() / 2 - bounds.height() / 2);
                break;

            case TOP:
                bounds.offsetTo(view.getWidth() / 2 - bounds.width() / 2,
                    view.getPaddingTop());
                break;

            case RIGHT:
                bounds.offsetTo(view.getWidth() - view.getPaddingRight() - bounds.width(),
                    view.getHeight() / 2 - bounds.height() / 2);
                break;

            case BOTTOM:
                bounds.offsetTo(view.getWidth() / 2 - bounds.width() / 2,
                    view.getHeight() - view.getPaddingBottom() - bounds.height());
                break;
        }

        return bounds;
    }

    /**
     * Expands {@link Rect} by given value in every direction relative to its center
     * @param source given {@link Rect}
     * @return result {@link Rect}
     */
    private Rect addFuzz(Rect source) {
        Rect result = new Rect();
        result.left = source.left - fuzz;
        result.right = source.right + fuzz;
        result.top = source.top - fuzz;
        result.bottom = source.bottom + fuzz;
        return result;
    }

    /**
     * Compound drawable touch-event handler
     * @param v wrapping view
     * @param drawableIndex index of compound drawable which recicved the event
     * @param drawableBounds {@link Rect} with compound drawable bounds relative to wrapping view.
     * Fuzz not included
     * @param event event with coordinated relative to wrapping view - i.e. within {@code drawableBounds}.
     * If using fuzz, may return negative coordinates.
     */
    protected abstract boolean onDrawableTouch(View v, int drawableIndex, Rect drawableBounds, MotionEvent event);
}

Now you can process any touch events on any compound drawable of any TextView you like this way:

textView1.setOnTouchListener(new CompoundDrawableTouchListener() {
            @Override
            protected void onDrawableTouch(View v, int drawableIndex, Rect drawableBounds, MotionEvent event) {
                switch(v.getId()) {
                    case R.id.textView1:
                        switch(drawableIndex) {
                            case CompoundDrawableTouchListener.RIGHT:
                                doStuff();
                                break;
                        }
                        break;
                }
            }
        });

Only interested in clicks? Just filter out by MotionEvent action:

/**
 * Handles compound drawable click events.
 * @see TextView#getCompoundDrawables()
 * @see TextView#setCompoundDrawablesRelativeWithIntrinsicBounds(int, int, int, int)
 * @see CompoundDrawableTouchListener
 */
public abstract class CompoundDrawableClickListener extends CompoundDrawableTouchListener {

    /**
     * Default constructor
     */
    public CompoundDrawableClickListener() {
        super();
    }

     /**
     * Constructor with fuzz
     * @param fuzz desired fuzz in px
     */
    public CompoundDrawableClickListener(int fuzz) {
        super(fuzz);
    }

    @Override
    protected void onDrawableTouch(View v, int drawableIndex, Rect drawableBounds, MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_UP) onDrawableClick(v, drawableIndex);
        return true;
    }

    /**
     * Compound drawable touch-event handler
     * @param v wrapping view
     * @param drawableIndex index of compound drawable which recicved the event
     */
    protected abstract void onDrawableClick(View v, int drawableIndex);
}

Again we can easily handle clicks on any compound drawable of any TextView:

textView1.setOnTouchListener(new CompoundDrawableClickListener() {
            @Override
            protected void onDrawableClick(View v, int drawableIndex) {
                switch(v.getId()) {
                    case R.id.textView1:
                        switch(drawableIndex) {
                            case CompoundDrawableTouchListener.RIGHT:
                                doStuff();
                                break;
                        }
                        break;
                }
            }
        });

Hope you liked it as I did. I will try to keep it updated here and in related gist if anything changes.

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梦该遗忘
5楼-- · 2019-01-01 05:00

Consider the following. It's not the most elegant solution but it works, I just tested it.

  1. Create a customized EditText class CustomEditText.java:

    import android.content.Context;
    import android.graphics.Rect;
    import android.graphics.drawable.Drawable;
    import android.util.AttributeSet;
    import android.view.MotionEvent;
    import android.widget.EditText;
    
    public class CustomEditText extends EditText
    {
      private Drawable dRight;
      private Rect rBounds;
    
      public CustomEditText(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
      }
      public CustomEditText(Context context, AttributeSet attrs) {
        super(context, attrs);
      }
      public CustomEditText(Context context) {
        super(context);
      }
    
      @Override
      public void setCompoundDrawables(Drawable left, Drawable top,
          Drawable right, Drawable bottom)
      {
        if(right !=null)
        {
          dRight = right;
        }
        super.setCompoundDrawables(left, top, right, bottom);
      }
    
      @Override
      public boolean onTouchEvent(MotionEvent event)
      {
    
        if(event.getAction() == MotionEvent.ACTION_UP && dRight!=null)
        {
          rBounds = dRight.getBounds();
          final int x = (int)event.getX();
          final int y = (int)event.getY();
          //System.out.println("x:/y: "+x+"/"+y);
          //System.out.println("bounds: "+bounds.left+"/"+bounds.right+"/"+bounds.top+"/"+bounds.bottom);
          //check to make sure the touch event was within the bounds of the drawable
          if(x>=(this.getRight()-rBounds.width()) && x<=(this.getRight()-this.getPaddingRight())
              && y>=this.getPaddingTop() && y<=(this.getHeight()-this.getPaddingBottom()))
          {
            //System.out.println("touch");
            this.setText("");
            event.setAction(MotionEvent.ACTION_CANCEL);//use this to prevent the keyboard from coming up
          }
        }
        return super.onTouchEvent(event);
      }
    
      @Override
      protected void finalize() throws Throwable
      {
        dRight = null;
        rBounds = null;
        super.finalize();
      }
    }
    
  2. Change your layout XML to this (where com.example is your actual project package name):

    <com.example.CustomEditText
        android:id="@+id/txtsearch"
        …
        android:layout_gravity="center_vertical"
        android:background="@layout/shape"
        android:hint="Enter place,city,state"
        android:drawableRight="@drawable/cross" 
    />
    
  3. Finally, add this (or something similar) to your activity:

    …
    CustomEditText et = (CustomEditText) this.findViewById(R.id.txtsearch);
    …
    

I might be a bit off with the calculation of the touch bounds for the nested drawable but you get the idea.

I hope this helps.

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不流泪的眼
6楼-- · 2019-01-01 05:00

Extending on the idea by RyanM I have created a more flexible version, which supports all the drawable types (top, bottom, left, right). While the code below extends TextView, adapting it for an EditText is just a case of swapping "extends TextView" with "extends EditText". Instantiation the widget from XML is identical as in RyanM's example, bar the widget name.


import android.content.Context;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.widget.TextView;

import com.example.DrawableClickListener.DrawablePosition;

public class ButtonTextView extends TextView {

private Drawable    drawableRight;
private Drawable    drawableLeft;
private Drawable    drawableTop;
private Drawable    drawableBottom;

private int     actionX, actionY;

private DrawableClickListener clickListener;

public ButtonTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
}

public ButtonTextView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public ButtonTextView(Context context) {
    super(context);
}

@Override
public void setCompoundDrawables(Drawable left, Drawable top, Drawable right, Drawable bottom) {
    if (right != null) {
        drawableRight = right;
    }

    if (left != null) {
        drawableLeft = left;
    }

    if (top != null) {
        drawableTop = top;
    }

    if (bottom != null) {
        drawableBottom = bottom;
    }

    super.setCompoundDrawables(left, top, right, bottom);
}

@Override
public boolean onTouchEvent(MotionEvent event) {

    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        actionX = (int) event.getX();
        actionY = (int) event.getY();

        if (drawableBottom != null && drawableBottom.getBounds().contains(actionX, actionY)) {
            clickListener.onClick(DrawablePosition.BOTTOM);
            return super.onTouchEvent(event);
        }

        if (drawableTop != null && drawableTop.getBounds().contains(actionX, actionY)) {
            clickListener.onClick(DrawablePosition.TOP);
            return super.onTouchEvent(event);
        }

        if (drawableLeft != null && drawableLeft.getBounds().contains(actionX, actionY)) {
            clickListener.onClick(DrawablePosition.LEFT);
            return super.onTouchEvent(event);
        }

        if (drawableRight != null && drawableRight.getBounds().contains(actionX, actionY)) {
            clickListener.onClick(DrawablePosition.RIGHT);
            return super.onTouchEvent(event);
        }
    }


    return super.onTouchEvent(event);
}

@Override
protected void finalize() throws Throwable {
    drawableRight = null;
    drawableBottom = null;
    drawableLeft = null;
    drawableTop = null;
    super.finalize();
}

public void setDrawableClickListener(DrawableClickListener listener) {
    this.clickListener = listener;
}}

The DrawableClickListener is as simple as this:

public interface DrawableClickListener {

public static enum DrawablePosition { TOP, BOTTOM, LEFT, RIGHT };
public void onClick(DrawablePosition target); }

And then the actual implementation:

class example implements DrawableClickListener {
public void onClick(DrawablePosition target) {
    switch (target) {
        case LEFT:
            doSomethingA();
            break;

        case RIGHT:
            doSomethingB();
            break;

        case BOTTOM:
            doSomethingC();
            break;

        case TOP:
            doSomethingD();
            break;

        default:
            break;
    }
}}

p.s.: If you don't set the listener, touching the TextView will cause a NullPointerException. You may want to add some more paranoia into the code.

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浪荡孟婆
7楼-- · 2019-01-01 05:01

Very, very good, thanks to everyone who contributed to this discussion. So if you don't want to deal with inconvenience of extending the class you can do the following (implemented for the right drawable only)

this.keyword = (AutoCompleteTextView) findViewById(R.id.search);
this.keyword.setOnTouchListener(new RightDrawableOnTouchListener(keyword) {
        @Override
        public boolean onDrawableTouch(final MotionEvent event) {
            return onClickSearch(keyword,event);
        }
    });

private boolean onClickSearch(final View view, MotionEvent event) {
    // do something
    event.setAction(MotionEvent.ACTION_CANCEL);
    return false;
}

And here's bare-bone listener implementation based on @Mark's answer

public abstract class RightDrawableOnTouchListener implements OnTouchListener {
    Drawable drawable;
    private int fuzz = 10;

    /**
     * @param keyword
     */
    public RightDrawableOnTouchListener(TextView view) {
        super();
        final Drawable[] drawables = view.getCompoundDrawables();
        if (drawables != null && drawables.length == 4)
            this.drawable = drawables[2];
    }

    /*
     * (non-Javadoc)
     * 
     * @see android.view.View.OnTouchListener#onTouch(android.view.View, android.view.MotionEvent)
     */
    @Override
    public boolean onTouch(final View v, final MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN && drawable != null) {
            final int x = (int) event.getX();
            final int y = (int) event.getY();
            final Rect bounds = drawable.getBounds();
            if (x >= (v.getRight() - bounds.width() - fuzz) && x <= (v.getRight() - v.getPaddingRight() + fuzz)
                    && y >= (v.getPaddingTop() - fuzz) && y <= (v.getHeight() - v.getPaddingBottom()) + fuzz) {
                return onDrawableTouch(event);
            }
        }
        return false;
    }

    public abstract boolean onDrawableTouch(final MotionEvent event);

}
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