当前项目知识点总结

1、输入框里输入密码是否显示明文

显示明文：etPass.setTransformationMethod(HideReturnsTransformationMethod
     .getInstance());

不显示明文：etPass.setTransformationMethod(PasswordTransformationMethod
     .getInstance());

2、联网操作最好放到onresum方法里面

3、代码控制imageview的透明度：choose_bg_cancel.getBackground().setAlpha(200);

4、拍照或者从本地获取图片当做头像

  拍照：Intent camera = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
   camera.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(pic));
   startActivityForResult(camera, PHOTOHRAPH);

相册：Intent photo = new Intent(Intent.ACTION_PICK, null);
   photo.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
     "image/*");
   startActivityForResult(photo, PHOTOZOOM);

并在onactivityresult方法中处理

裁剪图片Intent intent = new Intent("com.android.camera.action.CROP");
  intent.setDataAndType(uri, "image/*");
  intent.putExtra("crop", "true");
  // aspectX aspectY 是宽高的比例
  intent.putExtra("aspectX", 1);
  intent.putExtra("aspectY", 1);
  // outputX outputY 是裁剪图片宽高
  intent.putExtra("outputX", 256);
  intent.putExtra("outputY", 256);
  intent.putExtra("return-data", true);

 

5、监听电量：在onreceive方法中用到

if (intent.getAction().equals(Intent.ACTION_BATTERY_CHANGED)) {
    // 获取当前的电量
    int level = intent.getIntExtra("level", 0);
    // 电量总刻度
    int scale = intent.getIntExtra("scale", 100);
    Message msg = new Message();
    msg.what = 1;
    msg.obj = (level * 100) / scale + "%";
    handler.sendMessage(msg);
   }