獲取Android控件尺寸

獲取系統的高度和寬度

/**
 * 獲取顯示屏幕的高度
 * @return
 */
private int getScreenHeight() {
	WindowManager windowManager = mainActivity.getWindowManager();
	Display display = windowManager.getDefaultDisplay();

	Point point = new Point();
	display.getSize(point);
	int SCREEN_WIDTH = point.x;
	int SCREEN_HEIGHT = point.y;

	// 或者
	DisplayMetrics dm = new DisplayMetrics();
	display.getMetrics(dm);
	int SCREEN_WIDTH = dm.widthPixels;
	int SCREEN_HEIGHT = dm.heightPixels;

	return SCREEN_HEIGHT;
}

/**
 * 獲取頂部status bar高度
 * @return
 */
private int getStatusBarHeight() {
	Resources resources = mContext.getResources();
	int resourceId = resources.getIdentifier("status_bar_height", "dimen","android");
	int height = resources.getDimensionPixelSize(resourceId);
	return height;
}

/**
 * 獲取底部 navigation bar 高度
 * @return
 */
private int getNavigationBarHeight() {
	Resources resources = mActivity.getResources();
	int resourceId = resources.getIdentifier("navigation_bar_height","dimen", "android");
	int height = resources.getDimensionPixelSize(resourceId);
	return height;
}

獲取控件的高度和寬度

1）安裝佈局監聽器

mView.getViewTreeObserver().addOnGlobalLayoutListener(
	new OnGlobalLayoutListener() {
		@Override
		public void onGlobalLayout(){                                             
			mViewHeight = mView.getHeight();
			//OnGlobalLayoutListener可能會被屢次觸發,因此註銷掉
			mView.getViewTreeObserver().removeGlobalOnLayoutListener(this);
		}
});

2）view的UI線程

mView.post(new Runnable() {
	@Override
	public void run() {
		mViewHeight = mView.getMeasuredWidth());
		}
	}
);

3）重寫Activity的方法

@Override
public void onWindowFocusChanged(boolean hasFocus) {
	super.onWindowFocusChanged(hasFocus);
	int[] location = new int[2];
	mView.getLocationOnScreen(location);
	mViewHeight = location[1];
}

系統調用順序爲

Activity.oncreate()→Activity.onResume()→
→TestImageView.onMeasure()→TestImageView.onLayout()→onGlobalLayoutListener()→
→Activity.onWidnowFocusChanged()→.....→
→TextImageView.onDraw()