Multi-State Toggle Button

问题:

In the app I've been working on, I would like to have a multiple-state (in my case, three) toggle button, instead of the two that ToggleButton provides. I've tried to start my own that extends Button, following the CompoundButton source, but quite honestly reading over its source got a bit overwhelming.

Is there a way to do a three-state toggle button using just a selector xml or something, or perhaps another method I haven't thought of? I'm rather at a loss of how to do this.

回答1:

You can certainly define a selector to use as a background that has three entries. The question is what button attributes you can use for the selector. You can have two boolean attributes, say A and B, and define the selector in terms of A, B, and default. (A && B will satisfy A, so more properly they could be thought of as A, !A && B, and !A && !B.) You can overload existing attributes (selected, focused, etc.) or, more elegantly, define your own custom attributes using the recipe described in this thread.

回答2:

I implemented a multi-state toggle button, the source code is here

This is how it looks:

And it's quite easy to use it:

<org.honorato.multistatetogglebutton.MultiStateToggleButton
    android:id="@+id/mstb_multi_id"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dip"
    mstb:values="@array/planets_array" />

In your activity:

MultiStateToggleButton button2 = (MultiStateToggleButton) this.findViewById(R.id.mstb_multi_id);
button2.setOnValueChangedListener(new ToggleButton.OnValueChangedListener() {
    @Override
    public void onValueChanged(int value) {
        Log.d(TAG, "Value: " + value);
    }
});

回答3:

You can create a custom ImageButton to achieve this, you need 3 different images in this case. You can also add more states if you want.

public class FlashButton extends ImageButton {

    public enum FlashEnum {
        AUTOMATIC, ON, OFF
    }

    public interface FlashListener {
        void onAutomatic();
        void onOn();
        void onOff();
    }

    private FlashEnum mState;
    private FlashListener mFlashListener;

    public FlashButton(Context context, AttributeSet attrs) {
        super(context, attrs);

        //Sets initial state
        setState(FlashEnum.AUTOMATIC);
    }


    @Override
    public boolean performClick() {
        super.performClick();
        int next = ((mState.ordinal() + 1) % FlashEnum.values().length);
        setState(FlashEnum.values()[next]);
        performFlashClick();
        return true;
    }


    private void performFlashClick() {
        if(mFlashListener == null)return;
        switch (mState) {
            case AUTOMATIC:
                mFlashListener.onAutomatic();
                break;
            case ON:
                mFlashListener.onOn();
                break;
            case OFF:
                mFlashListener.onOff();
                break;
        }
    }

    private void createDrawableState() {
        switch (mState) {
            case AUTOMATIC:
                setImageResource(R.drawable.ic_flash_auto);
                break;
            case ON:
                setImageResource(R.drawable.ic_flash_on);
                break;
            case OFF:
                setImageResource(R.drawable.ic_flash_off);
                break;
        }
    }


    public FlashEnum getState() {
        return mState;
    }

    public void setState(FlashEnum state) {
        if(state == null)return;
        this.mState = state;
        createDrawableState();

    }

    public FlashListener getFlashListener() {
        return mFlashListener;
    }

    public void setFlashListener(FlashListener flashListener) {
        this.mFlashListener = flashListener;
    }

}

回答4:

Why not use RadioGroup and style radios inside?

 <RadioGroup
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal">

    <RadioButton
        android:layout_width="match_parent"
        android:layout_weight="1"
        android:layout_height="wrap_content"
        android:background="@drawable/your_drawable_selector"
        android:button="@android:color/transparent"
        android:gravity="center_horizontal" //center text
        android:text="text"
         />
...