EditText和setOnKeyListener事件实现文本处理
package com.example.test12;
import android.os.Bundle;
import android.app.Activity;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.support.v4.app.NavUtils;
public class MainActivity extends Activity {
private TextView text;
private EditText edit;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
text=(TextView)findViewById(R.id.textView1);
edit=(EditText)findViewById(R.id.editText1);
edit.setOnKeyListener(editlistener);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
View.OnKeyListener editlistener=new View.OnKeyListener() {
public boolean onKey(View v, int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
text.setText(edit.getText());
return false;
}
};
}
带背景图片的按钮
使用ImageButton来实现带背景图片的按钮。
OnFocusChangeListener焦点变化监听
ImageButton.setImageResourse()用来指定按钮的背景颜色
package com.example.test13;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.TextView;
import android.support.v4.app.NavUtils;
public class MainActivity extends Activity {
private TextView tv;
private ImageButton ibt;
private Button bt;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv=(TextView)findViewById(R.id.textView1);
ibt=(ImageButton)findViewById(R.id.imageButton1);
bt=(Button)findViewById(R.id.button1);
ibt.setOnFocusChangeListener(focusChange);
bt.setOnClickListener(clicked);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
View.OnFocusChangeListener focusChange=new View.OnFocusChangeListener() {
public void onFocusChange(View v, boolean hasFocus) {
// TODO Auto-generated method stub
if(hasFocus){
tv.setText("Got Focus!!!");
ibt.setImageResource(R.drawable.image1);
}
else{
tv.setText("Lost Focus!!!");
ibt.setImageResource(R.drawable.image2);
}
}
};
View.OnClickListener clicked=new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
if(tv.getText()=="Got Focus!!!"){
tv.setText("Lost Focus!!!");
ibt.setImageResource(R.drawable.image2);
}
else{
tv.setText("Got Focus!!!");
ibt.setImageResource(R.drawable.image1);
}
}
};
}
Toast实现提示条(Toast总结)
Toast.makeText()让文字显示与Toast对象中,会显示一段时间后自动消失。
Toast.makeText(
MainActivity.this,
"这个是Toast.makeText提示",
Toast.LENGTH_LONG).show();
CheckBox和RadioButton复选框
通过CheckBox.setOnCheckedChangeLister来监听CheckBox
相框的实现
可以通过ImageButton和ImageView来实现,推荐ImageButton,它可以直接添加点击监听
java.io.File实现文件搜索
在JAVA I/O的API中,提供了java.io.File对象。
package com.example.test14;
import java.io.File;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import android.support.v4.app.NavUtils;
public class MainActivity extends Activity {
private TextView result;
private Button bt;
private EditText edit;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
result=(TextView)findViewById(R.id.textView2);
bt=(Button)findViewById(R.id.button1);
edit=(EditText)findViewById(R.id.editText1);
bt.setOnClickListener(new Button.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
String keyword=edit.getText().toString();
if(keyword.equals("")){
Toast.makeText(
MainActivity.this,
"不能为空!",
Toast.LENGTH_LONG).show();
}
else{
result.setText(searchFile(keyword));
}
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
private String searchFile(String Keyword){
String searchResult="";
File[] files=new File("/").listFiles();
for(File f:files){
if(f.getName().indexOf(Keyword)>=0)
searchResult+=f.getPath()+"\n";// \n换行
}
if(searchResult.equals(""))
searchResult="找不到文件!!!!";
return searchResult;
}
}
本文转自cococo点点博客园博客,原文链接:http://www.cnblogs.com/coder2012/archive/2013/05/17/3083991.html,如需转载请自行联系原作者