我有一个 RemoteCar 应用程序，可以调节空调、启动引擎等。在我的 MainActivity 中有一个 FuelBar 和一个 SeekBar(AC)。我想保存这些实例以供下次运行。例如，当我将空调设置为 20° 并关闭应用程序时，我希望空调打开 20°，就像我离开它的方式一样。但不知何故，我把编码搞砸了，以至于它甚至不再启动，你能解释一下我错过了什么吗？
在 C++ 中，我可以轻松地打开一个文件并立即关闭它，但是“close()”方法不太有效。我也很欣赏与此主题相关的任何信息，我可以在其中阅读。
保存方法“saveInfo”并在 onStop 中我希望它保存当前状态。
package com.example.schwarzerritter.remotecv02;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.Toast;
import org.w3c.dom.Text;
import static com.example.schwarzerritter.remotecv02.R.id.engB;
import static com.example.schwarzerritter.remotecv02.R.id.fuelProgressBar;
import static com.example.schwarzerritter.remotecv02.R.id.refuelB;
import static com.example.schwarzerritter.remotecv02.R.id.seekBar;
public class MainActivity extends AppCompatActivity {
public ProgressBar fuelBar;
public Button lockButton;
public Button engButton;
public Button refuelButton;
public Button locationButton;
public SeekBar seekBarButton;
public TextView seekText;
int incFuel = 0;
public void onClick(View v) {
switch (v.getId()) {
case engB:
if (engButton.getText() == "ENGINE RUNNING") {
engButton.setText("START ENGINE");
} else {
if (fuelBar.getProgress() > 0) {
Toast.makeText(MainActivity.this, "starting engine..", Toast.LENGTH_SHORT).show();
engButton.setText("ENGINE RUNNING");
if (fuelBar.getProgress() >= 10) {
incFuel = fuelBar.getProgress();
incFuel -= 10;
fuelBar.setProgress(incFuel);
if (fuelBar.getProgress() < 100)
refuelButton.setText("REFUEL");
}
} else if (fuelBar.getProgress() == 0) {
Toast.makeText(MainActivity.this, "no fuel", Toast.LENGTH_SHORT).show();
engButton.setText("EMPTY GASTANK");
} else
engButton.setText("START ENGINE");
}
break;
case refuelB:
if (fuelBar.getProgress() == 0) {
engButton.setText("START ENGINE");
incFuel = fuelBar.getProgress();
incFuel += 10;
fuelBar.setProgress(incFuel);
} else if (fuelBar.getProgress() < 100) {
incFuel = fuelBar.getProgress();
incFuel += 10;
fuelBar.setProgress(incFuel);
} else {
Toast.makeText(MainActivity.this, "tank is full", Toast.LENGTH_SHORT).show();
refuelButton.setText("FULL");
}
break;
}
}
public void seek_bar() {
seekBarButton = (SeekBar) findViewById(R.id.seekBar);
seekText = (TextView) findViewById(R.id.seekText);
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
seekBarButton.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
int progressNum;
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
progressNum = progress;
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
seekText.setText("AC : " + (seekBarButton.getProgress() + 18) + "°");
}
});
}
public void saveInfo() {
SharedPreferences sharedPref = getSharedPreferences("conditions", 0);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("seekBar", seekText.getText().toString());
editor.putInt("refuelBar", fuelBar.getProgress());
editor.commit();
}
public void lockPage() {
lockButton = (Button) findViewById(R.id.lockB);
lockButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent lockPage = new Intent(MainActivity.this, lockDoor.class);
startActivity(lockPage);
}
});
}
public void locationPage() {
locationButton = (Button) findViewById(R.id.locationB);
locationButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent locationPage = new Intent(MainActivity.this, location.class);
startActivity(locationPage);
}
});
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
saveInfo();//read files
locationButton = (Button) findViewById(R.id.locationB);
lockButton = (Button) findViewById(R.id.lockB);
engButton = (Button) findViewById(R.id.engB);
refuelButton = (Button) findViewById(R.id.refuelB);
fuelBar = (ProgressBar) findViewById(R.id.fuelProgressBar);
fuelBar.setMax(100);
fuelBar.setProgress(30);
refuelButton.setText(R.string.refuelB);
lockButton.setText(R.string.lockB);
locationButton.setText(R.string.locationB);
engButton.setText(R.string.engB);
seekBarButton = (SeekBar) findViewById(R.id.seekBar);
seekText = (TextView) findViewById(R.id.seekText);
seek_bar();
lockPage();
locationPage();
}
protected void onStop(){
super.onStop();
//Open SharedPref
SharedPreferences sharedPref = getSharedPreferences("conditions", 0);
//Edit
SharedPreferences.Editor editor = sharedPref.edit();
//Write file
editor.putString("seekBar", seekText.getText().toString());
editor.putInt("refuelBar", fuelBar.getProgress());
//save
editor.commit();
//editor.close; Error: can't resolve method/symbol close
}
}
日志猫：
05-24 08:00:54.870 2026-2040/com.google.process.gapps W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/user/0/com.google.android.gsf/databases/gservices.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:00:55.040 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/networkstatistics.sqlite' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:28:52.605 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/auto_complete_suggestions.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:28:52.605 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/help_responses.db.18' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:28:52.606 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/metrics.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:29:04.497 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/auto_complete_suggestions.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:29:04.499 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/help_responses.db.18' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:29:04.499 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/metrics.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:30:52.533 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/metrics.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:30:52.535 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/help_responses.db.18' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:30:52.541 2146-2157/com.google.android.gms W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.google.android.gms/databases/auto_complete_suggestions.db' was leaked! Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
05-24 08:31:07.294 1796-1796/com.google.android.googlequicksearchbox W/IInputConnectionWrapper: showStatusIcon on inactive InputConnection
05-24 08:31:51.101 3983-4041/com.google.android.gms I/FA-SVC: App measurement is starting up, version: 10298
05-24 08:31:51.190 3983-4199/com.google.android.gms I/FA-SVC: This instance being marked as an uploader