我是一名新的 Android 开发人员，在开始一项提供项目列表详细信息的新活动时遇到问题。
我的第一个活动是列出智能手机上安装的所有应用程序。当我单击此列表中的一个项目时，第二个活动开始显示该项目的详细信息。
但是，我的 onSaveInstanceState 方法允许我在每次切换智能手机位置时都不会重新加载应用程序，它似乎被发送到详细活动并进入无限循环（或者由于位图的序列化而非常长）字节缓冲区）。
我的 PInfo 对象是包含所有应用程序信息（版本、名称、位图）的对象。
public class PInfo implements Serializable{
private static final long serialVersionUID = 1L;
private String appname = "";
private String pname = "";
private String versionName = "";
private int versionCode = 0;
private Bitmap icon ;
private static ByteBuffer dst;
private static byte[] bytesar;
public String getAppname() {
return appname;
}
public void setAppname(String appname) {
this.appname = appname;
}
public String getPname() {
return pname;
}
public void setPname(String pname) {
this.pname = pname;
}
public String getVersionName() {
return versionName;
}
public void setVersionName(String versionName) {
this.versionName = versionName;
}
public int getVersionCode() {
return versionCode;
}
public void setVersionCode(int versionCode) {
this.versionCode = versionCode;
}
public Bitmap getIcon() {
return icon;
}
public void setIcon(Bitmap icon) {
this.icon = icon;
}
private void writeObject(ObjectOutputStream out) throws IOException{
out.writeObject(appname);
out.writeObject(pname);
out.writeObject(versionName);
out.writeInt(versionCode);
out.writeInt(icon.getRowBytes());
out.writeInt(icon.getHeight());
out.writeInt(icon.getWidth());
int bmSize = icon.getRowBytes() * icon.getHeight();
if(dst==null || bmSize > dst.capacity())
dst= ByteBuffer.allocate(bmSize);
out.writeInt(dst.capacity());
dst.position(0);
icon.copyPixelsToBuffer(dst);
if(bytesar==null || bmSize > bytesar.length)
bytesar=new byte[bmSize];
dst.position(0);
dst.get(bytesar);
out.write(bytesar, 0, bytesar.length);
}
private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException{
appname=(String) in.readObject();
pname=(String) in.readObject();
versionName=(String) in.readObject();
versionCode= in.readInt();
int nbRowBytes=in.readInt();
int height=in.readInt();
int width=in.readInt();
int bmSize=in.readInt();
if(bytesar==null || bmSize > bytesar.length)
bytesar= new byte[bmSize];
int offset=0;
while(in.available()>0){
offset=offset + in.read(bytesar, offset, in.available());
}
if(dst==null || bmSize > dst.capacity())
dst= ByteBuffer.allocate(bmSize);
dst.position(0);
dst.put(bytesar);
dst.position(0);
icon=Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
icon.copyPixelsFromBuffer(dst);
//in.close();
}
我的列表活动：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_application_list);
if (savedInstanceState != null) {
apps = (ArrayList<PInfo>) savedInstanceState.getSerializable("apps");
} else {
apps = new ArrayList<PInfo>();
apps = getInstalledApps(false);
}
appAdapter = new AppAdapter(apps);
setListAdapter(appAdapter);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long index) {
AppAdapter appAdapter = new AppAdapter(apps);
PInfo app = appAdapter.getItem(position);
Intent intent = new Intent(ApplicationListActivity.this,ApplicationDetailActivity.class);
//intent.putExtra("app", app);
intent.putExtra("app_index", index);
startActivity(intent);
}
private ArrayList<PInfo> getInstalledApps(boolean getSysPackages) {
ArrayList<PInfo> res = new ArrayList<PInfo>();
List<PackageInfo> packs = getPackageManager().getInstalledPackages(0);
for(int i=0;i<packs.size();i++) {
PackageInfo p = packs.get(i);
if ((!getSysPackages) && (p.versionName == null)) {
continue ;
}
PInfo newInfo = new PInfo();
newInfo.setAppname(p.applicationInfo.loadLabel(getPackageManager()).toString());
newInfo.setPname(p.packageName);
newInfo.setVersionName(p.versionName);
newInfo.setVersionCode(p.versionCode);
Drawable d = p.applicationInfo.loadIcon(getPackageManager());
Bitmap bitmap = ((BitmapDrawable)d).getBitmap();
newInfo.setIcon(bitmap);
res.add(newInfo);
}
return res;
}
@Override
protected void onSaveInstanceState(Bundle outState) {
outState.putSerializable("apps", apps);
super.onSaveInstanceState(outState);
}
我的详细活动：
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_application_detail);
//PInfo p = (PInfo)getIntent().getExtras().getSerializable("app");
PackageInfo p = getPackageManager().getInstalledPackages(0).get((int)getIntent().getExtras().getLong("app_index"));
appName = (TextView) findViewById(R.id.appName);
versionName = (TextView) findViewById(R.id.versionName);
detailIcon = (ImageView) findViewById(R.id.detailIcon);
appName.setText(p.applicationInfo.loadLabel(getPackageManager()).toString());
versionName.setText(p.versionName);
detailIcon.setImageDrawable(p.applicationInfo.loadIcon(getPackageManager()));
}
来自 logCat 的部分消息（只是无限循环的一部分；））：
10-31 15:06:53.065: D/dalvikvm(3406): GC_CONCURRENT freed 0K, 20% free 45150K/55751K, paused 12ms+8ms,总共32ms
10-31 15:06:53.065: D/dalvikvm(3406): WAIT_FOR_CONCURRENT_GC 阻塞 20ms
10-31 15:06:53.100: D/dalvikvm(3406): GC_CONCURRENT freed 1013K, 18% free 46177K/55751K, paused 12ms+3ms,总共33ms
10-31 15:06:53.100: D/dalvikvm(3406): WAIT_FOR_CONCURRENT_GC 阻塞 21ms
10-31 15:06:53.115: D/dalvikvm(3406): GC_FOR_ALLOC 释放 0K，18% 释放 46177K/55751K，暂停 13ms，总共 13ms
10-31 15:06:53.115：I/dalvikvm-heap(3406)：将堆（碎片情况）增加到 47.644MB，分配 2105798 字节
10-31 15:06:53.145: D/dalvikvm(3406): GC_CONCURRENT freed 1027K, 16% free 47206K/55751K, paused 12ms+3ms,总共30ms
10-31 15:06:53.145: D/dalvikvm(3406): WAIT_FOR_CONCURRENT_GC 阻塞 16ms
10-31 15:06:53.160: D/dalvikvm(3406): GC_FOR_ALLOC freed 0K, 16% free 47206K/55751K, paused 15ms,总共15ms
10-31 15:06:53.165：I/dalvikvm-heap(3406)：将堆（碎片情况）增加到 50.659MB，分配 4213190 字节
10-31 15:06:53.195: D/dalvikvm(3406): GC_CONCURRENT freed 6664K, 20% free 44656K/55751K, paused 12ms+3ms,总共32ms
10-31 15:06:53.195: D/dalvikvm(3406): WAIT_FOR_CONCURRENT_GC 阻塞 19ms
- 我想知道当我开始我的详细活动时发生了什么？
- 这个循环是否将所有应用程序中的所有位图序列化到 ByteBuffer 中？
- 如何在不启动此循环的情况下启动我的详细活动？
我希望我已经足够清楚了，对于最终的拼写错误，我深表歉意。