本文實例講述了Android編程獲取屏幕寬高與獲取控件寬高的方法。分享給大家供大家參考,具體如下:
獲取屏幕寬高
// 獲取屏幕寬高(方法1)int screenWidth = getWindowManager().getDefaultDisplay().getWidth(); // 屏幕寬(像素,如:480px)int screenHeight = getWindowManager().getDefaultDisplay().getHeight(); // 屏幕高(像素,如:800p)Log.e(TAG + " getDefaultDisplay", "screenWidth=" + screenWidth + "; screenHeight=" + screenHeight);// 獲取屏幕密度(方法2)DisplayMetrics dm = new DisplayMetrics();dm = getResources().getDisplayMetrics();float density = dm.density; // 屏幕密度(像素比例:0.75/1.0/1.5/2.0)int densityDPI = dm.densityDpi; // 屏幕密度(每寸像素:120/160/240/320)float xdpi = dm.xdpi;float ydpi = dm.ydpi;Log.e(TAG + " DisplayMetrics", "xdpi=" + xdpi + "; ydpi=" + ydpi);Log.e(TAG + " DisplayMetrics", "density=" + density + "; densityDPI=" + densityDPI);screenWidth = dm.widthPixels; // 屏幕寬(像素,如:480px)screenHeight = dm.heightPixels; // 屏幕高(像素,如:800px)Log.e(TAG + " DisplayMetrics(111)", "screenWidth=" + screenWidth + "; screenHeight=" + screenHeight);// 獲取屏幕密度(方法3)dm = new DisplayMetrics();getWindowManager().getDefaultDisplay().getMetrics(dm);density = dm.density; // 屏幕密度(像素比例:0.75/1.0/1.5/2.0)densityDPI = dm.densityDpi; // 屏幕密度(每寸像素:120/160/240/320)xdpi = dm.xdpi;ydpi = dm.ydpi;Log.e(TAG + " DisplayMetrics", "xdpi=" + xdpi + "; ydpi=" + ydpi);Log.e(TAG + " DisplayMetrics", "density=" + density + "; densityDPI=" + densityDPI);int screenWidthDip = dm.widthPixels; // 屏幕寬(dip,如:320dip)int screenHeightDip = dm.heightPixels; // 屏幕寬(dip,如:533dip)Log.e(TAG + " DisplayMetrics(222)", "screenWidthDip=" + screenWidthDip + "; screenHeightDip=" + screenHeightDip);screenWidth = (int)(dm.widthPixels * density + 0.5f); // 屏幕寬(px,如:480px)screenHeight = (int)(dm.heightPixels * density + 0.5f); // 屏幕高(px,如:800px)Log.e(TAG + " DisplayMetrics(222)", "screenWidth=" + screenWidth + "; screenHeight=" + screenHeight);
獲取控件的寬高
一般來說,我們在onCreate里面得到的控件的寬高全是0.采用下面的方法,可以得到真實的寬高
方法一:
int w = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED);int h = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED);imageView.measure(w, h);int height =imageView.getMeasuredHeight();int width =imageView.getMeasuredWidth();textView.append("/n"+height+","+width);此方法會加載onMeasure三次
方法二:
ViewTreeObserver vto = imageView.getViewTreeObserver();vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() { public boolean onPreDraw() { int height = imageView.getMeasuredHeight(); int width = imageView.getMeasuredWidth(); textView.append("/n"+height+","+width); return true; }});此方法會加載onMeasure二次,但是回調函數會回調很多次
方法三:
ViewTreeObserver vto2 = imageView.getViewTreeObserver();vto2.addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { imageView.getViewTreeObserver().removeGlobalOnLayoutListener(this); textView.append("/n/n"+imageView.getHeight()+","+imageView.getWidth()); }});此方法會加載onMeasure二次,但是回調函數只回調一次
希望本文所述對大家Android程序設計有所幫助。
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