Android: Ruled/horizontal lines in Textview

问题:

In Android, I have a TextView and its content will be dynamic. I want to show a horizontal line after each line of text. I have searched a lot and found it for EditText( How to use ruled/horizontal lines to align text in EditText in Android?). I was planing to draw dynamic TextView and a horizontal line under them. But I don't know how can I detect an end of line. Any help will be highly appreciated. I want to have the same effect as the attached image of How to use ruled/horizontal lines to align text in EditText in Android?

回答1:

I'm using the technique of drawing lines between each line of text in EditText and then I will make the EditText non-editable by setting setKeyListener(null) to the custom EditText object so that, the EditText acts like a TextView :)

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A custom EditText that draws lines between each line of text that is displayed:

public class LinedEditText extends EditText {
    private Rect mRect;
    private Paint mPaint;

    // we need this constructor for LayoutInflater
    public LinedEditText(Context context, AttributeSet attrs) {
        super(context, attrs);

        mRect = new Rect();
        mPaint = new Paint();
        mPaint.setStyle(Paint.Style.STROKE);
        mPaint.setColor(0x800000FF);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        int count = getLineCount();
        Rect r = mRect;
        Paint paint = mPaint;

        for (int i = 0; i < count; i++) {
            int baseline = getLineBounds(i, r);

            canvas.drawLine(r.left, baseline + 1, r.right, baseline + 1, paint);
        }

        super.onDraw(canvas);
    }
} 

---

Now use object of LinedEditText class where you need your TextView and make it non-editable.

An Example:

public class HorizontalLine extends Activity{
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {   
        super.onCreate(savedInstanceState);
        setTitle("Android: Ruled/horizonal lines in Textview");

        LinearLayout ll = new LinearLayout(this);
        ll.setOrientation(LinearLayout.VERTICAL);
        LayoutParams textViewLayoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

        LinedEditText et = new LinedEditText(this, null);
        et.setText("The name of our country is Bangladesh. I am proud of my country :)");
        et.setLayoutParams(textViewLayoutParams);
        et.setKeyListener(null);

        ll.addView(et);
        this.setContentView(ll);

    }

}

---

et.setKeyListener(null) makes the EditText non-editable so, it acts like a TextView.

---

The Output:

Issue with cursor:

If you use et.setKeyListener(null) only then it is just not listening to keys but user can see a cursor on the EditText. If you don't want this cursor just disable the EditText by adding this line:

 et.setEnabled(false);

回答2:

You can use a View for drawing line: For horizontal line:

<View
android:layout_height="1dp"
android:layout_width="fill_parent"
android:background="#ffffff" />

回答3:

<TextView  
android:layout_height="1dp"  
android:layout_width="fill_parent"/>