<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:orientation="horizontal" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="200dp"
        android:layout_height="400dp"
        android:src="@drawable/tmp_image4" />
 
</LinearLayout>
 

先看程式碼部分

public class MainActivity extends Activity {
	
	private ImageView imageView;
	private String TAG="debug";
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		imageView=(ImageView)findViewById(R.id.imageView1);
		
		Log.d(TAG, "---->"+imageView.getHeight()+"  "+imageView.getWidth());
	}
}
 

imageView.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				Log.d(TAG, "---->"+imageView.getHeight()+"  "+imageView.getWidth());
			}
		});

為什麼是600 300 因為xml單位是dp 程式碼中是px  因此會差一點 但是每次獲取控制元件的寬高都需要onclik 有點費事

ViewTreeObserver viewTreeObserver = imageView.getViewTreeObserver();
		viewTreeObserver.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
			@SuppressWarnings("deprecation")
			@Override
			public void onGlobalLayout() {
				imageView.getViewTreeObserver().removeGlobalOnLayoutListener(
						this);
				Log.d(TAG,
						"---->" + imageView.getHeight() + "  "+ imageView.getWidth());

			}
		});
 

還是600 300 並且不需要點選事件就可以直接列印  再來說一下 px和dp的轉換 

		ViewTreeObserver viewTreeObserver = imageView.getViewTreeObserver();
		viewTreeObserver
				.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
					@SuppressWarnings("deprecation")
					@Override
					public void onGlobalLayout() {
						imageView.getViewTreeObserver()
								.removeGlobalOnLayoutListener(this);
						Log.d(TAG, "---->" + px2dip(MainActivity.this, imageView.getHeight()) + "  "
								+ px2dip(MainActivity.this, imageView.getWidth()));

					}
				});
	}
	//dp->px
	public static int dip2px(Context context, float dpValue) {
		final float scale = context.getResources().getDisplayMetrics().density;
		return (int) (dpValue * scale + 0.5f);
	}
	//px->dp
	public static int px2dip(Context context, float pxValue) {
		final float scale = context.getResources().getDisplayMetrics().density;
		return (int) (pxValue / scale + 0.5f);
	}

08-01 18:19:47.016: D/debug(8928): ---->400  200  

搞定  當時找到的時候忘記記下出處 現在翻出來沒有標註 見諒……