• ColorFilter 修改图片颜色，滤镜
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public static Drawable filtDrawable(Drawable drawable, int color) {
    ColorFilter filter = new LightingColorFilter(0, color);
    drawable.setColorFilter(filter);
    return drawable;
}

相关文章 http://www.cnblogs.com/fuxiuyuan/archive/2012/04/14/2447545.html

  • 获取 StatusBar 高度
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public static float getStatusBarHeight(Activity activity) {
    Resources resources = activity.getResources();
    int status_bar_height_id = resources.getIdentifier("status_bar_height", "dimen", "android");
    return resources.getDimension(status_bar_height_id);
}
  • 获取 ActionBar 的视图
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public static View findActionBarContainer(Activity activity) {
    int id = activity.getResources().getIdentifier("action_bar_container", "id", "android");
    return activity.findViewById(id);
}
public static View findSplitActionBar(Activity activity) {
    int id = activity.getResources().getIdentifier("split_action_bar", "id", "android");
    return activity.findViewById(id);
}
  • 计算文字大小绘制需要的宽高
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Rect rect = new Rect();
mPaint.getTextBounds(text, 0, text.length(), rect);
rect.width();
rect.height()；
  • Activity 中可以获取 Actionbar 上 Item 的 View
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getActivity().findViewById(R.id.menu_favorite); //
  • java.lang.IllegalStateException: No activity
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@Override
public void onDetach() {
super.onDetach();
    try {
        Field childFragmentManager = Fragment.class.getDeclaredField("mChildFragmentManager");
        childFragmentManager.setAccessible(true);
        childFragmentManager.set(this, null);
    } catch (NoSuchFieldException e) {
        throw new RuntimeException(e);
    } catch (IllegalAccessException e) {
        throw new RuntimeException(e);
    }
}
  • 保存恢复 ListView 位置
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private void saveCurrentPosition() {
    if (mListView != null) {
        int position = mListView.getFirstVisiblePosition();
        View v = mListView.getChildAt(0);
        int top = (v == null) ? 0 : v.getTop();
        //保存position和top
    }
}

private void restorePosition() {
    if (mFolder != null && mListView != null) {
        int position = 0;//取出保存的数据
        int top = 0;//取出保存的数据
        mListView.setSelectionFromTop(position, top);
    }
}