Android開發20——單個監聽器監聽多個按鈕點擊事件

本文出自 “IT徐胖子的專欄” 博客，請務必保留此出處http://woshixy.blog.51cto.com/5637578/1093936

一、單個按鈕點擊事件的監聽

方法一

/**
 * 從網絡上獲取圖片
 *
 * @author 徐越
 *
 */
publicclass MainActivity extends Activity
{
private EditText txtPath;
private Button btnShowImage;
private ImageView imgView;

@Override
publicvoid onCreate(Bundle savedInstanceState)
    {
super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        txtPath = (EditText) this.findViewById(R.id.txtPath);
        btnShowImage = (Button) this.findViewById(R.id.btnShowImage);
        imgView = (ImageView) this.findViewById(R.id.imgView);
        btnShowImage.setOnClickListener(new ShowImageListener());
    }

privatefinalclass ShowImageListener implements View.OnClickListener
    {
@Override
publicvoid onClick(View v)
        {
// 圖片路徑
            String path = txtPath.getText().toString();
try
            {
// 獲取圖片的二進制數據
byte[] imgdata = ImageService.getImage(path);
// 利用Bitmap工廠生成Bitmap
                Bitmap bitmap = BitmapFactory.decodeByteArray(imgdata, 0, imgdata.length);
// imageView接收Bitmap並顯示
                imgView.setImageBitmap(bitmap);
            }
catch (Exception e)
            {
                Toast.makeText(MainActivity.this, "讀取圖片失敗", Toast.LENGTH_SHORT).show();
            }
        }
    }
}

方法二

在佈局頁面中給該按鈕加上android:onClick="showImage"，然後再顯示該元素的Activity中加入showImage(View v)的方法，在該方法中進行操作。

二、多個按鈕點擊事件的監聽

方法一

在Activity中按照第一個大標題的方法，給每個按鈕寫一個監聽類或者監聽方法。

方法二

利用一個監聽器監聽所有按鈕的點擊事件

/**
 * 查詢號碼歸屬地
 *
 * @author 徐越
 *
 */
publicclass MainActivity extends Activity implements View.OnClickListener
{
private EditText txtPhone;
private TextView lblAddress;
private Button btnQuery;
private Button btnReset;
private CallAddressQueryService callAddressQueryService = new CallAddressQueryService();
privatefinalint CLICK_QUERY = 1;
privatefinalint CLICK_RESET = 2;

@Override
publicvoid onCreate(Bundle savedInstanceState)
    {
super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        lblAddress = (TextView) this.findViewById(R.id.lblAddress);
        txtPhone = (EditText) this.findViewById(R.id.txtPhone);
        btnQuery = (Button) this.findViewById(R.id.btnQuery);
        btnReset = (Button) this.findViewById(R.id.btnReset);
        btnQuery.setOnClickListener(this);
        btnQuery.setTag(CLICK_QUERY);
        btnReset.setOnClickListener(this);
        btnReset.setTag(CLICK_RESET);
    }

@Override
publicvoid onClick(View v)
    {
int tag = (Integer) v.getTag();
switch (tag)
        {
case CLICK_QUERY:
                query();
break;
case CLICK_RESET:
                reset();
break;
        }
    }

publicvoid query()
    {
        String phone = txtPhone.getText().toString();
try
        {
            lblAddress.setText("查詢中");
            String address = callAddressQueryService.getCallAddress(phone);
            lblAddress.setText(address);
        }
catch (Exception e)
        {
            e.printStackTrace();
            Toast.makeText(this, "查詢失敗", Toast.LENGTH_LONG).show();
        }
    }

publicvoid reset()
    {
        txtPhone.setText("");
        lblAddress.setText("");
    }
}

本文出自 “IT徐胖子的專欄” 博客，請務必保留此出處http://woshixy.blog.51cto.com/5637578/1093936