TextView的使用方法
布局文件中的配置:
在Activity类中的使用:
TextView textView1 = (TextView)findViewById(R.id.textView1);
textView1.setText(R.string.username);
EditText的使用方法
布局文件中的配置:
在Activity类中的使用:
EditText editText1 = (EditText)findViewById(R.id.editText1);
Button的使用方法
布局文件中的配置:
在Activity类中的使用:
Button button1 = (Button)findViewById(R.id. button1);
//TestListener为继承OnClickListener的类
button1.setOnClickListener(new TestListener());
Menu的使用方法
onCreateOptionsMenu(Menu menu)
Initialize the contents of the Activity's standard options menu.
onCreateOptionsMenu是Activity中的一个方法,当用户点击了MENU按钮时,Activity会触发该方法,Menu的创建在这里执行:
@Override
public boolean onCreateOptionsMenu(Menu menu) {
menu.add(0, 1, 1, R.string.back);
menu.add(0,2,2,R.string.exit);
return super.onCreateOptionsMenu(menu);
}
为按钮添加方法,需要实现Activity的onOptionsItemSelected方法:
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if(item.getItemId() == 2){
finish();
}
return super.onOptionsItemSelected(item);
}
RadioGroup和RadioButton
布局文件的编写:
在Activity中使用:
RadioGroup radioGroup1 = (RadioGroup)findViewById(R.id.radioGroup1);
RadioButton radioButton1 = (RadioButton)findViewById(R.id.femaleButton);
RadioButton radioButton2 = (RadioButton)findViewById(R.id. radioButton2);
为RadioGroup设置监听器,使用RadioGroup.OnCheckedChangeListener类
radioGroup1.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
if(radioButton1.getId() == checkedId){
System.out.println("radioButton1");
}
else if(radioButton2.getId() == checkedId)
{
System.out.println("radioButton2");
}
}
});
CheckBox
布局文件的编写:
在Activity中的使用:
CheckBox checkBox1 = (CheckBox)findViewById(R.id.checkBox1);
CheckBox checkBox2 = (CheckBox)findViewById(R.id.checkBox2);
为多选按钮添加监听器,这里使用CompoundButton.OnCheckedChangeListener
checkBox1.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked)
{
System.out.println("checkBox1 is checked");
}
else
{
System.out.println("checkBox1 is unchecked");
}
}
});
checkBox2.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(isChecked)
{
System.out.println("checkBox2 is checked");
}
else
{
System.out.println("checkBox2 is unchecked");
}
}
});
Toast
public class
Toast
extends Object
A toast is a view containing a quick little message for the user. The toast class helps you create and show those.
直接在Activity中使用:
Toast.makeText(RadioTest.this, "checkBox1", Toast.LENGTH_SHORT).show();
ProgressBar
在布局文件中编写:
在Activity中使用:
ProgressBar progressBar1 = (ProgressBar)findViewById(R.id.progressBar1);
这里使用一个鼠标点击事件触发处理该进度条:
private int i = 0;
class ButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
if(i == 0) {
progressBar1.setVisibility(View.VISIBLE);
progressBar1.setMax(100);
}
else if ( i < progressBar1.getMax()){
progressBar1.setProgress(i);
progressBar1.setSecondaryProgress(i + 10);
}
else{
progressBar1.setVisibility(View.GONE);
}
i = i + 10 ;
}
}
ListView
public class
ListView
extends AbsListView
A view that shows items in a vertically scrolling list. The items come from the ListAdapter associated with this view.
要使用ListView必须继承ListActivity类,同时需要在代码中构造 一个android.widget.SimpleAdapter类,用于辅助创建ListView。除此之外还需要创建另外一个布局文件供ListView使用:
主布局文件的编写:
另外需要一个布局文件供ListView使用:
继承ListActivity的类
public class ActivityTest extends ListActivity {…}
在该类中生成ListView:
setContentView(R.layout.main);
ArrayList> list = new ArrayList>();
HashMap map1 = new HashMap();
HashMap map2 = new HashMap();
HashMap map3 = new HashMap();
map1.put("user_name", "arthinking");
map1.put("user_id", "001");
map2.put("user_name", "Jason");
map2.put("user_id", "002");
list.add(map1);
list.add(map2);
SimpleAdapter listAdapter = new SimpleAdapter(this, list,
R.layout.user, new String[]{"user_name","user_id"},
new int[]{R.id.user_name,R.id.user_id});
setListAdapter(listAdapter);
要实现监听事件,可以实现ListActivity的onListItemClick方法:
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
System.out.println(id);
}