我正在尝试通过单击按钮启动活动
日志
10-21 15:26:58.747: D/AndroidRuntime(693): Shutting down VM
10-21 15:26:58.747: W/dalvikvm(693): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
10-21 15:26:58.767: E/AndroidRuntime(693): FATAL EXCEPTION: main
10-21 15:26:58.767: E/AndroidRuntime(693): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.androidbegin.jsonparsetutorial/com.project.findmybuffet.Filters}: java.lang.NullPointerException
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.os.Handler.dispatchMessage(Handler.java:99)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.os.Looper.loop(Looper.java:123)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread.main(ActivityThread.java:4627)
10-21 15:26:58.767: E/AndroidRuntime(693): at java.lang.reflect.Method.invokeNative(Native Method)
10-21 15:26:58.767: E/AndroidRuntime(693): at java.lang.reflect.Method.invoke(Method.java:521)
10-21 15:26:58.767: E/AndroidRuntime(693): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-21 15:26:58.767: E/AndroidRuntime(693): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-21 15:26:58.767: E/AndroidRuntime(693): at dalvik.system.NativeStart.main(Native Method)
10-21 15:26:58.767: E/AndroidRuntime(693): Caused by: java.lang.NullPointerException
10-21 15:26:58.767: E/AndroidRuntime(693): at com.project.findmybuffet.Filters.onCreate(Filters.java:181)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
10-21 15:26:58.767: E/AndroidRuntime(693): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
10-21 15:26:58.767: E/AndroidRuntime(693): ... 11 more
10-21 15:27:42.949: I/Process(693): Sending signal. PID: 693 SIG: 9
过滤器.java
public class Filters extends Activity implements OnSeekBarChangeListener{
// declare text objects variables
private SeekBar PRICEbar,DISTANCEbar, RATINGbar;
private TextView PRICEtextProgress,DISTANCEtextProgress, RATINGtextProgress;
Button back;
Button FILTER;
private RadioGroup rdg;
private RadioButton indian;
private RadioButton thai;
private RadioButton chinese;
private String selectedType="";
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
// load the layout
setContentView(R.layout.filters);
/** Finding all the views in this Activity. */
PRICEbar = (SeekBar)findViewById(R.id.PRICEseekBarID); // make seekbar object
DISTANCEbar = (SeekBar)findViewById(R.id.DISTANCEseekBarID); // make seekbar object
RATINGbar = (SeekBar)findViewById(R.id.RATINGseekBarID); // make seekbar object
FILTER=(Button) findViewById(R.id.SEARCH_BUTTON_ID);
rdg = (RadioGroup) findViewById(R.id.radioGroup1);
indian = (RadioButton) findViewById(R.id.IndianRG_ID);
thai = (RadioButton) findViewById(R.id.ThaiRG_ID);
chinese = (RadioButton) findViewById(R.id.ChineseRG_ID);
back=(Button) findViewById(R.id.TopNavigationBarFilterBackButton);
back.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
finish();
}
});
PRICEbar.setOnSeekBarChangeListener(this);
PRICEbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
PRICEtextProgress = (TextView)findViewById(R.id.PRICEtextViewProgressID);
PRICEtextProgress.setText("Price:: Rs "+progress);
seekBar.setMax(100);
}
});
////////////////////////////////////////////////////////
DISTANCEbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
DISTANCEtextProgress = (TextView)findViewById(R.id.DISTANCEtextViewProgressID);
DISTANCEtextProgress.setText("Distance:: "+progress);
seekBar.setMax(25);
}
});
////////////////////////////////////////////////////////
RATINGbar.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress,
boolean fromUser) {
// TODO Auto-generated method stub
RATINGtextProgress = (TextView)findViewById(R.id.RATINGtextViewProgressID);
RATINGtextProgress.setText("Rating:: "+progress);
seekBar.setMax(5);
RatingBar ratingBar = (RatingBar)findViewById(R.id.RATINGfinalvalueratingID);
ratingBar.setRating(5);
ratingBar.setFocusable(false);
RatingBar ratingBar1 = (RatingBar)findViewById(R.id.RATINGinitialvalueratingID);
ratingBar1.setRating(0);
ratingBar.setFocusable(false);
}
});
rdg.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
if(i==R.id.BreakfastRG_ID){
selectedType = indian.getText().toString();
}else if(i==R.id.LunchRG_ID){
selectedType = thai.getText().toString();
}else{
selectedType = chinese.getText().toString();
}
}
});
FILTER.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent FilterIntent=new Intent(Filters.this,AndroidTabRestaurantDescSearchListView.class);
FilterIntent.putExtra("REST1",selectedType);
FilterIntent.putExtra("PriceBar", PRICEbar.getProgress());
FilterIntent.putExtra("DistanceBar", DISTANCEbar.getProgress());
FilterIntent.putExtra("RatingBar", RATINGbar.getProgress());
startActivity(FilterIntent);
}
});
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
if (seekBar == PRICEbar)
PRICEtextProgress.setText("Price:: Rs "+progress);
else if (seekBar == DISTANCEbar)
DISTANCEtextProgress.setText("Distance:: "+progress);
else if (seekBar == RATINGbar)
RATINGtextProgress.setText("Rating:: "+progress);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
// TODO Auto-generated method stub
}
}
放置此代码后出现错误
FILTER.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent FilterIntent=new Intent(Filters.this,AndroidTabRestaurantDescSearchListView.class);
FilterIntent.putExtra("REST1",selectedType);
FilterIntent.putExtra("PriceBar", PRICEbar.getProgress());
FilterIntent.putExtra("DistanceBar", DISTANCEbar.getProgress());
FilterIntent.putExtra("RatingBar", RATINGbar.getProgress());
startActivity(FilterIntent);
}
});
该代码用于启动新活动，因此它是必不可少的
我应该把代码放在哪里filter.java
- 当我单击按钮启动活动时，我得到
null pointer exception 因为我没有将任何价值从一项活动传递到另一项活动
如何解决这个问题