Android StateListDrawable 按下状态总是显示最后添加的。

Question

我有一个自定义按钮，通过编程方式更改了其按下和默认颜色。

public class CustomApplicationButton extends Button {

public CustomApplicationButton(Context context) {
    this(context, 0, 0, 0);
}

public CustomApplicationButton(Context context, int topDrawableResId, int outlineDefaultColorId, int outlinePressedColorId) {
    super(context);

    // set width and height
    LinearLayout.LayoutParams params = new LayoutParams(
            context.getResources().getDimensionPixelSize(R.dimen.sr_application_button_width), 
            context.getResources().getDimensionPixelSize(R.dimen.sr_application_button_height));
    setLayoutParams(params);

    // set drawable top icon
    if (topDrawableResId != 0) {
        setCompoundDrawablesWithIntrinsicBounds(0, topDrawableResId, 0, 0);
    }

    // set background and outline color

    int strokeWidth = context.getResources().getDimensionPixelSize(R.dimen.sr_launcher_button_stroke_size);

    // unpressed state drawable
    LayerDrawable defaultLayers = (LayerDrawable) context.getResources().getDrawable(
            R.drawable.btn_launcher_shape_default);
    GradientDrawable defaultShapeOutline = (GradientDrawable) defaultLayers.findDrawableByLayerId(R.id.outline_default);
    defaultShapeOutline.setStroke(strokeWidth, context.getResources().getColor(outlineDefaultColorId));

    // pressed state drawable
    LayerDrawable pressedLayers = (LayerDrawable) context.getResources().getDrawable(
            R.drawable.btn_launcher_shape_pressed);
    GradientDrawable pressedShapeOutline = (GradientDrawable) pressedLayers.findDrawableByLayerId(R.id.outline_pressed);
    pressedShapeOutline.setStroke(strokeWidth, context.getResources().getColor(outlinePressedColorId));

    // set states
    StateListDrawable states = new StateListDrawable();
    states.addState(new int[] {android.R.attr.state_pressed}, pressedLayers);
    states.addState(new int[] { }, defaultLayers);

    // set background
    this.setBackground(states);
}

然后，我在我的活动中添加了一个按钮，它内部有一个Linearlayout。

public class MainActivity extends Activity {

private LinearLayout applicationPanel;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    applicationPanel = (LinearLayout) findViewById(R.id.application_panel);
    ssPanel = (LinearLayout) findViewById(R.id.ss_panel);

    CustomApplicationButton btnLauncherApp = new CustomApplicationButton(this, R.drawable.ic_application, 
            R.color.application_green_default_color, R.color.application_green_pressed_color);
    btnLauncherApp.setText("Button 1");
    applicationPanel.addView(btnLauncherApp);

    btnLauncherApp = new CustomApplicationButton(this, R.drawable.ic_camera, 
            R.color.camera_blue_default_color, R.color.camera_blue_pressed_color);
    btnLauncherApp.setText("Button 2");
    applicationPanel.addView(btnLauncherApp);

    btnLauncherApp = new CustomApplicationButton(this, R.drawable.ic_browser, 
            R.color.browser_gray_default_color, R.color.browser_gray_pressed_color);
    btnLauncherApp.setText("Button 3");
    applicationPanel.addView(btnLauncherApp);

}

我的问题是，所有三个按钮都有不同的默认描边颜色，但按下时的描边颜色始终是最后添加的按钮颜色。

总之；

两张图片胜过千言万语 :)

- yasinkafadar

Answer 1

正如文档中清楚地提到的：

"Note: changing this property will affect all instances of a drawable loaded from a resource. It is recommended to invoke mutate() before changing this property."

所以，如果您在每次调用setStroke()之前调用mutate()，您的问题将得到解决。

defaultShapeOutline.mutate();
defaultShapeOutline.setStroke(strokeWidth, context.getResources().getColor(outlineDefaultColorId));

- CanC