5.7

mac2022-06-30 24

public void onClick(View v) { switch (v.getId()) { case R.id.btn_main_test1://常用简单的 startActivity(new Intent(this,SimpleComponent.class)); break;

@Override public void onClick(View v) { //得到内容 String number = et_simple_num.getText().toString().trim(); //提示 Toast.makeText(SimpleComponent.this, number, Toast.LENGTH_SHORT).show(); } }); iv_simple_play = (ImageView) findViewById(R.id.iv_simple_play); iv_simple_play.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub if (status) { //设置背景图片 iv_simple_play.setBackgroundResource(android.R.drawable.alert_light_frame); //设置前景图片 iv_simple_play.setImageResource(android.R.drawable.ic_media_pause); status=false; }else{ //设置背景图片 iv_simple_play.setBackgroundResource(android.R.drawable.alert_dark_frame); //设置前景图片 iv_simple_play.setImageResource(android.R.drawable.ic_media_play); status=true; } } }); cb_simple_football = (CheckBox) findViewById(R.id.cb_simple_football); cb_simple_lan = (CheckBox) findViewById(R.id.cb_simple_lan); cb_simple_pingpong = (CheckBox) findViewById(R.id.cb_simple_pingpong); //设置选中状态改变的监听 cb_simple_football.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { // TODO Auto-generated method stub if (isChecked) { Toast.makeText(SimpleComponent.this, "选中了篮球", Toast.LENGTH_SHORT).show(); }else{ Toast.makeText(SimpleComponent.this, "取消选中篮球", Toast.LENGTH_SHORT).show(); } } }); rg_simple_sex = (RadioGroup) findViewById(R.id.rg_simple_sex); rg_simple_sex.setOnCheckedChangeListener(new OnCheckedChangeListener() { @Override public void onCheckedChanged(RadioGroup group, int checkedId) { // checkedId就是选中的radiobutton的id //找到选中的radiobutton RadioButton radiobutton=(RadioButton) findViewById(checkedId); }

//提示 Toast.makeText(SimpleComponent.this, "lll", 2).show();

常见的异常: 1. NullPointerException 原因: 调用对象的方法/属性，但是对象为null 2. ClassCastException 原因: 类型转换异常 3. ActivityNotFoundException: 原因: 没有在清单文件中注册Activity,或注册不正确基本常见异常的一般分析步骤: 1. 在lagcat中从上向下找，尽量找到Caused by(会显示有那中异常导致的) 2. 找出异常的类以及行号，双击进入对应的行

转载于:https://www.cnblogs.com/feng8026/p/9006276.html