安卓新手。我在 GridView 中创建了 12 个(3 行,4 列)按钮,并按照教程创建了一个 toast 以在按下按钮后显示某些内容。按钮在屏幕上正确显示,但 toast 消息不正确。当我按下左上角的按钮时,我得到左下角的吐司。当我按下左中按钮时,我得到右中吐司。当我按下左下角的按钮时,我得到右上角的吐司。
Visually:
button location:
1 2 3 4
5 6 7 8
9 10 11 12
toast message
9 10 11 12
8 7 6 5
4 3 2 1
这是适配器代码:
public class KeypadAdapter extends BaseAdapter {
private Context mContext;
// Declare button click listener variable
private OnClickListener mOnButtonClick;
// Method to set button click listener variable
public void setOnButtonClickListener(OnClickListener listener) {
mOnButtonClick = listener;
}
public KeypadAdapter(Context c) {
mContext = c;
}
public int getCount() {
return mButtons.length;
}
public Object getItem(int position) {
return mButtons[position];
}
public long getItemId(int position) {
return 0;
}
private KeypadButtons[] mButtons = { KeypadButtons.ADD,
KeypadButtons.SUBTRACT, KeypadButtons.MULTIPLY,
KeypadButtons.DIVIDE, KeypadButtons.DET, KeypadButtons.INV,
KeypadButtons.POW2, KeypadButtons.POWN, KeypadButtons.TRANSPOSE,
KeypadButtons.NORM1, KeypadButtons.NORM2, KeypadButtons.NORMINF };
@Override
public View getView(int position, View convertView, ViewGroup parent) {
Button btn;
if (convertView == null) { // if it's not recycled, initialize some
// attributes
btn = new Button(mContext);
KeypadButtons keypadButton = mButtons[position];
if (keypadButton != KeypadButtons.DUMMY) {
btn.setOnClickListener(mOnButtonClick);
}
// Set CalculatorButton enumeration as tag of the button so that we
// will use this information from our main view to identify what to
// do
btn.setTag(keypadButton);
} else {
btn = (Button) convertView;
}
btn.setText(mButtons[position].getText());
return btn;
}
}
这是活动代码
public class MainActivity extends Activity {
GridView mKeypadGrid;
KeypadAdapter mKeypadAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Get reference to the keypad button GridView
mKeypadGrid = (GridView) findViewById(R.id.gridView);
// Create Keypad Adapter
mKeypadAdapter = new KeypadAdapter(this);
// Set adapter of the keypad grid
mKeypadGrid.setAdapter(mKeypadAdapter);
// Set button click listener of the keypad adapter
mKeypadAdapter.setOnButtonClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Button btn = (Button) v;
// Get the KeypadButton value which is used to identify the
// keypad button from the Button's tag
KeypadButtons keypadButton = (KeypadButtons) btn.getTag();
// Process keypad button
ProcessKeypadInput(keypadButton);
}
});
mKeypadGrid.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
}
});
}
protected void ProcessKeypadInput(KeypadButtons keypadButton) {
// TODO Auto-generated method stub
Toast.makeText(
MainActivity.this,
keypadButton.getText().toString() + " "
+ keypadButton.toString(), Toast.LENGTH_SHORT).show();
}
}
起初,祝酒的顺序似乎颠倒了。所以我试着做
KeypadButtons keypadButton = mButtons[mButtons.length - 1 - position];
这固定了底部的两行,但他的顶部行仍然颠倒了。
提前致谢。