Java 让异步任务开始工作
我正在尝试启动一个异步任务 但是当我运行应用程序时，acctivity崩溃了 我的任务：Java 让异步任务开始工作,java,android,function,android-asynctask,Java,Android,Function,Android Asynctask,我正在尝试启动一个异步任务 但是当我运行应用程序时，acctivity崩溃了 我的任务： private class HideTask extends AsyncTask<String, Void, String> { protected void onPreExecute() { //loader.show(); } protected void onPostExecute(String result) { //load
private class HideTask extends AsyncTask<String, Void, String> {
protected void onPreExecute() {
//loader.show();
}
protected void onPostExecute(String result) {
//loader.dismiss();
}
@Override
protected String doInBackground(String... params) {
//hide();
return "done";
}
}
公共类应用程序扩展活动实现OnClickListener{
私人按钮；
私人按钮选项；
私人编辑文本；
私有文本视图文件夹\u至\u隐藏；
对话进程；
字符串隐藏或显示；
字符串密码；
串通；
字符串目录；
ProgressDialog loader=ProgressDialog.show（App.this，“”，
“正在加载。请稍候…”，正确）；
/**在首次创建活动时调用*/
@凌驾
创建时的公共void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
setContentView（R.layout.main）；
//按钮；
按钮=（按钮）findViewById（R.id.button1）；
setOnClickListener（此）；
选项=（按钮）findViewById（R.id.button2）；
options.setOnClickListener（此选项）；
//编辑文本编辑文本
edittext=（edittext）findViewById（R.id.editText1）；
//TextView文件夹要隐藏；
文件夹_to_hide=（TextView）findViewById（R.id.textView1）；
init（）；
对话框（）；
速率（）；
}
私有类HideTask扩展异步任务{
受保护的void onPreExecute（）{
//loader.show（）；
}
受保护的void onPostExecute（字符串结果）{
//loader.discouse（）；
}
@凌驾
受保护的字符串doInBackground（字符串…参数）{
//隐藏（）；
返回“完成”；
}
}
公共void init（）{
尝试
{
布尔exists2=（新文件（“/data/data/folder.hide.alexander.fuchs/folder.db”））.exists（）；
如果（存在2）{
setText（反序列化字符串（“/data/data/folder.hide.alexander.fuchs/folder.db”）；
}
否则{
edittext.setText（“/sdcard/Hide”）；
createfolder（“/sdcard/Hide”）；
}
布尔存在=（新文件（“/data/data/folder.hide.alexander.fuchs/hide.db”））.exists（）；
如果（存在）{
edittext.setVisibility（View.INVISIBLE）；
文件夹\u到\u hide.setVisibility（视图不可见）；
隐藏或显示=“显示”；
按钮设置文本（“显示”）；
}否则{
隐藏或显示=“隐藏”；
按钮设置文本（“隐藏”）；
}
}
捕获（异常x）
{
}
}
公用void createfolder（字符串路径）{
尝试
{
新文件（路径）.mkdirs（）；
}
捕获（异常x）
{
完成（）；
}
}
//删除目录下的所有文件和子目录。
//如果所有删除都成功，则返回true。
//如果删除失败，该方法将停止尝试删除并返回false。
公共静态布尔deleteDir（文件目录）{
if（dir.isDirectory（））{
String[]children=dir.list（）；
对于（int i=0；i 0）{
out.write（缓冲区，0，长度）；
}
in.close（）；
out.close（）；
系统
HideTask task = new HideTask();
task.execute(new String[] { "" });
public class App extends Activity implements OnClickListener {
private Button button;
private Button options;
private EditText edittext;
private TextView folder_to_hide;
Dialog progress;
String hide_or_show;
String password;
String pass;
String directory;
ProgressDialog loader = ProgressDialog.show(App.this, "",
"Loading. Please wait...", true);
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Button button;
button = (Button) findViewById(R.id.button1);
button.setOnClickListener(this);
options = (Button) findViewById(R.id.button2);
options.setOnClickListener(this);
// EditText edittext
edittext = (EditText) findViewById(R.id.editText1);
//TextView folder_to_hide;
folder_to_hide = (TextView) findViewById(R.id.textView1);
init();
dialog();
rate();
}
private class HideTask extends AsyncTask<String, Void, String> {
protected void onPreExecute() {
//loader.show();
}
protected void onPostExecute(String result) {
//loader.dismiss();
}
@Override
protected String doInBackground(String... params) {
//hide();
return "done";
}
}
public void init() {
try
{
boolean exists2 = (new File("/data/data/folder.hide.alexander.fuchs/folder.db")).exists();
if (exists2) {
edittext.setText(deserializeString("/data/data/folder.hide.alexander.fuchs/folder.db"));
}
else {
edittext.setText("/sdcard/Hide");
createfolder("/sdcard/Hide");
}
boolean exists = (new File("/data/data/folder.hide.alexander.fuchs/hide.db")).exists();
if (exists) {
edittext.setVisibility(View.INVISIBLE);
folder_to_hide.setVisibility(View.INVISIBLE);
hide_or_show = "show";
button.setText("Show");
} else {
hide_or_show = "hide";
button.setText("Hide");
}
}
catch(Exception x)
{
}
}
public void createfolder(String path) {
try
{
new File(path).mkdirs();
}
catch(Exception x)
{
finish();
}
}
// Deletes all files and subdirectories under dir.
// Returns true if all deletions were successful.
// If a deletion fails, the method stops attempting to delete and returns false.
public static boolean deleteDir(File dir) {
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i=0; i<children.length; i++) {
boolean success = deleteDir(new File(dir, children[i]));
if (!success) {
return false;
}
}
}
// The directory is now empty so delete it
return dir.delete();
}
/**
public void copyDirectory(File sourceLocation , File targetLocation)
throws IOException {
if (sourceLocation.isDirectory()) {
if (!targetLocation.exists()) {
targetLocation.mkdir();
}
String[] children = sourceLocation.list();
for (int i=0; i<children.length; i++) {
copyDirectory(new File(sourceLocation, children[i]),
new File(targetLocation, children[i]));
}
} else {
InputStream in = new FileInputStream(sourceLocation);
OutputStream out = new FileOutputStream(targetLocation);
// Copy the bits from instream to outstream
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
out.write(buf, 0, len);
}
in.close();
out.close();
}
}
**/
public static void copyFolder(File src, File dest)
throws IOException{
if(src.isDirectory()){
//if directory not exists, create it
if(!dest.exists()){
dest.mkdir();
System.out.println("Directory copied from "
+ src + " to " + dest);
}
//list all the directory contents
String files[] = src.list();
for (String file : files) {
//construct the src and dest file structure
File srcFile = new File(src, file);
File destFile = new File(dest, file);
//recursive copy
copyFolder(srcFile,destFile);
}
}else{
//if file, then copy it
//Use bytes stream to support all file types
InputStream in = new FileInputStream(src);
OutputStream out = new FileOutputStream(dest);
byte[] buffer = new byte[1024];
int length;
//copy the file content in bytes
while ((length = in.read(buffer)) > 0){
out.write(buffer, 0, length);
}
in.close();
out.close();
System.out.println("File copied from " + src + " to " + dest);
}
}
@Override
public void onClick(View v) {
if (v == button)
{
try
{
directory = edittext.getText().toString();
FileWriter fstream = new FileWriter("/data/data/folder.hide.alexander.fuchs/folder.db");
BufferedWriter out = new BufferedWriter(fstream);
out.write(directory);
//Close the output stream
out.close();
if(hide_or_show == "hide")
{
HideTask task = new HideTask();
task.execute(new String[] { "http://www.vogella.de" });
edittext.setVisibility(View.INVISIBLE);
folder_to_hide.setVisibility(View.INVISIBLE);
}
else
{
show();
edittext.setVisibility(View.VISIBLE);
folder_to_hide.setVisibility(View.VISIBLE);
}
}
catch(Exception x)
{
String ErrorMessage = x.getMessage();
Toast.makeText(this,"Error"+ErrorMessage, Toast.LENGTH_LONG).show();
finish();
}
}
if (v == options)
{
final CharSequence[] items = {"Change password", "http://www.alexander-fuchs.net/", "Market"};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Options");
builder.setItems(items, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int item) {
if (items[item] == "Change password")
{
createpass();
}
if (items[item] == "http://www.alexander-fuchs.net/")
{
intentstarter(items[item].toString());
toaster(items[item].toString());
}
if (items[item] == "Market")
{
intentstarter("market://search?q=pub:Alexander Fuchs");
toaster("Please wait...");
}
}
});
AlertDialog alert = builder.create();
alert.show();
}
}
public void hide() {
try
{
FileWriter fstream = new FileWriter("/data/data/folder.hide.alexander.fuchs/hide.db");
BufferedWriter out = new BufferedWriter(fstream);
out.write("hide");
//Close the output stream
out.close();
File copy = new File(directory);
File target = new File("/data/data/folder.hide.alexander.fuchs/Hide");
copyFolder(copy,target);
deleteDir(copy);
hide_or_show = "show";
button.setText("Show");
}
catch(Exception x)
{
edittext.setVisibility(View.VISIBLE);
folder_to_hide.setVisibility(View.VISIBLE);
File copy = new File("/data/data/folder.hide.alexander.fuchs/folder.db");
deleteDir(copy);
copy = new File("/data/data/folder.hide.alexander.fuchs/hide.db");
deleteDir(copy);
String ErrorMessage = x.getMessage();
Toast.makeText(this,"Error", Toast.LENGTH_LONG).show();
finish();
}
}
public void show() {
try
{
File delete = new File("/data/data/folder.hide.alexander.fuchs/hide.db");
deleteDir(delete);
File target = new File(directory);
File copy = new File("/data/data/folder.hide.alexander.fuchs/Hide");
copyFolder(copy,target);
deleteDir(copy);
hide_or_show = "hide";
button.setText("Hide");
}
catch(Exception x)
{
String ErrorMessage = x.getMessage();
Toast.makeText(this,"Error", Toast.LENGTH_LONG).show();
finish();
}
}
public void dialog() {
//set up dialog
final Dialog dialog = new Dialog(App.this);
dialog.setContentView(R.layout.dialoglayout);
dialog.setTitle("Password");
dialog.setCancelable(false);
//there are a lot of settings, for dialog, check them all out!
//set up text
final EditText text = (EditText) dialog.findViewById(R.id.editText1);
text.setText("");
//set up button
Button button = (Button) dialog.findViewById(R.id.Button01);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
password = text.getText().toString();
try
{
pass = deserializeString("/data/data/folder.hide.alexander.fuchs/password.db");
}
catch(Exception x)
{
String ErrorMessage = x.getMessage();
toaster("Error");
finish();
}
if(password.equals(pass))
{
dialog.dismiss();
}
else
{
toaster("Invalid Password");
finish();
}
}
});
//now that the dialog is set up, it's time to show it
boolean exists = (new File("/data/data/folder.hide.alexander.fuchs/password.db")).exists();
if (exists) {
dialog.show();
}
else
{
createpass();
}
}
public static String deserializeString(String file)
throws IOException {
int len;
char[] chr = new char[4096];
final StringBuffer buffer = new StringBuffer();
final FileReader reader = new FileReader(file);
try {
while ((len = reader.read(chr)) > 0) {
buffer.append(chr, 0, len);
}
} finally {
reader.close();
}
return buffer.toString();
}
public void toaster(String text) {
Toast.makeText(this,text, Toast.LENGTH_LONG).show();
}
public void intentstarter(String string) {
String url = string;
Intent i = new Intent(Intent.ACTION_VIEW);
i.setData(Uri.parse(url));
startActivity(i);
}
public void dialogbuilder(String text) {
new AlertDialog.Builder(this).setMessage(
text).setNeutralButton(
"OK",
null).show();
}
public void createpass() {
//set up dialog
final Dialog dialog = new Dialog(App.this);
dialog.setContentView(R.layout.createpass);
dialog.setTitle("Set Password");
dialog.setCancelable(false);
//there are a lot of settings, for dialog, check them all out!
//set up text
final EditText text = (EditText) dialog.findViewById(R.id.editText1);
text.setText("");
//set up text
final EditText text2 = (EditText) dialog.findViewById(R.id.editText2);
text2.setText("");
//set up button
Button button = (Button) dialog.findViewById(R.id.Button01);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
String createpass_password = text.getText().toString().trim();
String createpass_password2 = text2.getText().toString().trim();
try
{
if(createpass_password.equals(createpass_password2))
{
FileWriter fstream = new FileWriter("/data/data/folder.hide.alexander.fuchs/password.db");
BufferedWriter out = new BufferedWriter(fstream);
out.write(createpass_password);
//Close the output stream
out.close();
dialog.dismiss();
dialogbuilder("Please notice that if you forget your password there is no availability to restore your data !");
}
else
{
toaster("Passwords are not matching !");
text.setText("");
text2.setText("");
}
}
catch(Exception x)
{
String ErrorMessage = x.getMessage();
toaster("Error");
finish();
}
}
});
//now that the dialog is set up, it's time to show it
dialog.show();
}
public void rate() {
//set up dialog
final Dialog dialog = new Dialog(App.this);
dialog.setContentView(R.layout.vote);
dialog.setTitle("Like this App ?");
dialog.setCancelable(true);
//there are a lot of settings, for dialog, check them all out!
//Rate
Button button = (Button) dialog.findViewById(R.id.button1);
//Later
Button button2 = (Button) dialog.findViewById(R.id.button2);
//No Thanks
Button button3 = (Button) dialog.findViewById(R.id.button3);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
try
{
// /data/data/folder.hide.alexander.fuchs/rate.db
FileWriter fstream = new FileWriter("/data/data/folder.hide.alexander.fuchs/rate.db");
BufferedWriter out = new BufferedWriter(fstream);
out.write("no");
//Close the output stream
out.close();
dialog.dismiss();
}
catch (Exception x)
{
}
intentstarter("market://details?id=folder.hide.alexander.fuchs");
toaster("Please wait...");
dialog.dismiss();
}
});
button2.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// /data/data/folder.hide.alexander.fuchs/rate.db
File dta = new File("/data/data/folder.hide.alexander.fuchs/rate.db");
deleteDir(dta);
dialog.dismiss();
}
});
button3.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
try
{
// /data/data/folder.hide.alexander.fuchs/rate.db
FileWriter fstream = new FileWriter("/data/data/folder.hide.alexander.fuchs/rate.db");
BufferedWriter out = new BufferedWriter(fstream);
out.write("no");
//Close the output stream
out.close();
dialog.dismiss();
}
catch (Exception x)
{
}
}
});
if (rate.rate() == 3)
{
dialog.show();
}
}
}
new HideTask().execute();