小姓程，请叫我序员的专栏

public class MainActivity extends Activity { private Button button; private ImageView imageViewOne; private ImageView imageViewTwo; @Override protected void onCreate(Bundle savedInstanceState) {

//当加载一张大图片的时候，会报内存溢出，所以我们必须把图片进行缩放public class MainActivity extends Activity { private ImageView imageView; private int width; private int height; @Override protected void onCreate(Bundle saved

android:scaleType是控制图片如何resized/moved来匹对ImageView的size。ImageView.ScaleType / android:scaleType值的意义区别：CENTER /center  按图片的原来size居中显示，当图片长/宽超过View的长/宽，则截取图片的居中部分显示CENTER_CROP / centerCrop  按

public class MainActivity extends Activity { private Button chooseButton; private ImageView imageView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstance

Activity启动方式有四种，分别是：standardsingleTopsingleTasksingleInstance可以根据实际的需求为Activity设置对应的启动模式，从而可以避免创建大量重复的Activity等问题。设置Activity的启动模式，只需要在AndroidManifest.xml里对应的标签设置android:launchMode属性，

Intent intent = new Intent();intent.setAction("android.media.action.IMAGE_CAPTURE");intent.addCategory("android.intent.category.DEFAULT");File file = new File(Environment.getExternalStorageDirecto