launcher修改--获取应用列表launcher源码解析

在home节面上，当我们点击中间按键的时候，会跳转到一个下图，

在代码中是如何实现的呢？我们来找一下：

mHandleView = (HandleView) findViewById(R.id.all_apps_button);
        mHandleView.setLauncher(this);
        mHandleView.setOnClickListener(this);
        mHandleView.setOnLongClickListener(this);

再看onclick()方法：在onclick方法中，有一下代码

else if (v == mHandleView) {
            if (isAllAppsVisible()) {
                closeAllApps(true);
            } else {
                showAllApps(true);
            }

我们再找一下showAllApps()方法

void showAllApps(boolean animated) {
        mAllAppsGrid.zoom(1.0f, animated);

        ((View) mAllAppsGrid).setFocusable(true);
        ((View) mAllAppsGrid).requestFocus();
        
        // TODO: fade these two too
        mDeleteZone.setVisibility(View.GONE);
        mHandleView.setVisibility(View.GONE);
        mPreviousView.setVisibility(View.GONE);
        mNextView.setVisibility(View.GONE);
	hotseatLeft.setVisibility(View.GONE);
	hotseatRight.setVisibility(View.GONE);
    }

在上面用到了mAllAppsGrid,我们找一下这个控件：

    private AllAppsView mAllAppsGrid;

       mAllAppsGrid = (AllAppsView)dragLayer.findViewById(R.id.all_apps_view);
 mAllAppsGrid.setLauncher(this);
 mAllAppsGrid.setDragController(dragController);
 ((View) mAllAppsGrid).setWillNotDraw(false); // We don't want a hole punched in our window.
 // Manage focusability manually since this thing is always visible
 ((View) mAllAppsGrid).setFocusable(false);

上面代码是在Launcher.java中的setupview()方法中定义
all_apps_view是在all_app_2d.xml中定义。

你想找到AllApp2D.java中，可以找到mAllAppsGrid使用的方法，如addApps，removeApps，zoom这几个方法：

public void addApps(ArrayList<ApplicationInfo> list) {
//        Log.d(TAG, "addApps: " + list.size() + " apps: " + list.toString());

        final int N = list.size();

        for (int i=0; i<N; i++) {
            final ApplicationInfo item = list.get(i);
            int index = Collections.binarySearch(mAllAppsList, item,
                    LauncherModel.APP_NAME_COMPARATOR);
            if (index < 0) {
                index = -(index+1);
            }
            mAllAppsList.add(index, item);
        }
        mAppsAdapter.notifyDataSetChanged();
    }

    public void removeApps(ArrayList<ApplicationInfo> list) {
        final int N = list.size();
        for (int i=0; i<N; i++) {
            final ApplicationInfo item = list.get(i);
            int index = findAppByComponent(mAllAppsList, item);
            if (index >= 0) {
                mAllAppsList.remove(index);
            } else {
                Log.w(TAG, "couldn't find a match for item \"" + item + "\"");
                // Try to recover.  This should keep us from crashing for now.
            }
        }
        mAppsAdapter.notifyDataSetChanged();
    }

    public void zoom(float zoom, boolean animate) {
// Log.d(TAG, "zooming " + ((zoom == 1.0) ? "open" : "closed"));
 cancelLongPress();

 mZoom = zoom;

 if (isVisible()) {
 getParent().bringChildToFront(this);
 setVisibility(View.VISIBLE);
 mGrid.setAdapter(mAppsAdapter);
 if (animate) {
 startAnimation(AnimationUtils.loadAnimation(getContext(), R.anim.all_apps_2d_fade_in));
 } else {
 onAnimationEnd();
 }
 } else {
 if (animate) {
 startAnimation(AnimationUtils.loadAnimation(getContext(), R.anim.all_apps_2d_fade_out));
 } else {
 onAnimationEnd();
 }
 }
 }

在zoom()方法里面有mGrid.setAdapter(mAppsAdapter)，在构造方法中，给adapter已经赋值。

public AllApps2D(Context context, AttributeSet attrs) {
        super(context, attrs);
        setVisibility(View.GONE);
        setSoundEffectsEnabled(false);

        mAppsAdapter = new AppsAdapter(getContext(), mAllAppsList);
        mAppsAdapter.setNotifyOnChange(false);
    }

那是如何获取应用列表的呢？我们再回到Launcher.java中，在loadHotseats()中：

 private void loadHotseats() {
        if (mHotseatConfig == null) {
            mHotseatConfig = getResources().getStringArray(R.array.hotseats);
            if (mHotseatConfig.length > 0) {
                mHotseats = new Intent[mHotseatConfig.length];
                mHotseatLabels = new CharSequence[mHotseatConfig.length];
                mHotseatIcons = new Drawable[mHotseatConfig.length];
            } else {
                mHotseats = null;
                mHotseatIcons = null;
                mHotseatLabels = null;
            }

            TypedArray hotseatIconDrawables = getResources().obtainTypedArray(R.array.hotseat_icons);
            for (int i=0; i<mHotseatConfig.length; i++) {
                // load icon for this slot; currently unrelated to the actual activity
                try {
                    mHotseatIcons[i] = hotseatIconDrawables.getDrawable(i);
                } catch (ArrayIndexOutOfBoundsException ex) {
                    Log.w(TAG, "Missing hotseat_icons array item #" + i);
                    mHotseatIcons[i] = null;
                }
            }
            hotseatIconDrawables.recycle();
        }

        PackageManager pm = getPackageManager();
        for (int i=0; i<mHotseatConfig.length; i++) {
            Intent intent = null;
            if (mHotseatConfig[i].equals("*BROWSER*")) {
                // magic value meaning "launch user's default web browser"
                // replace it with a generic web request so we can see if there is indeed a default
                String defaultUri = getString(R.string.default_browser_url);
                intent = new Intent(
                        Intent.ACTION_VIEW,
                        ((defaultUri != null)
                            ? Uri.parse(defaultUri)
                            : getDefaultBrowserUri())
                    ).addCategory(Intent.CATEGORY_BROWSABLE);
                // note: if the user launches this without a default set, she
                // will always be taken to the default URL above; this is
                // unavoidable as we must specify a valid URL in order for the
                // chooser to appear, and once the user selects something, that 
                // URL is unavoidably sent to the chosen app.
            } else {
                try {
                    intent = Intent.parseUri(mHotseatConfig[i], 0);
                } catch (java.net.URISyntaxException ex) {
                    Log.w(TAG, "Invalid hotseat intent: " + mHotseatConfig[i]);
                    // bogus; leave intent=null
                }
            }
            
            if (intent == null) {
                mHotseats[i] = null;
                mHotseatLabels[i] = getText(R.string.activity_not_found);
                continue;
            }

            if (LOGD) {
                Log.d(TAG, "loadHotseats: hotseat " + i 
                    + " initial intent=[" 
                    + intent.toUri(Intent.URI_INTENT_SCHEME)
                    + "]");
            }

            ResolveInfo bestMatch = pm.resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY);
            List<ResolveInfo> allMatches = pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
            if (LOGD) { 
                Log.d(TAG, "Best match for intent: " + bestMatch);
                Log.d(TAG, "All matches: ");
                for (ResolveInfo ri : allMatches) {
                    Log.d(TAG, "  --> " + ri);
                }
            }
            // did this resolve to a single app, or the resolver?
            if (allMatches.size() == 0 || bestMatch == null) {
                // can't find any activity to handle this. let's leave the 
                // intent as-is and let Launcher show a toast when it fails 
                // to launch.
                mHotseats[i] = intent;

                // set accessibility text to "Not installed"
                mHotseatLabels[i] = getText(R.string.activity_not_found);
            } else {
                boolean found = false;
                for (ResolveInfo ri : allMatches) {
                    if (bestMatch.activityInfo.name.equals(ri.activityInfo.name)
                        && bestMatch.activityInfo.applicationInfo.packageName
                            .equals(ri.activityInfo.applicationInfo.packageName)) {
                        found = true;
                        break;
                    }
                }
                
                if (!found) {
                    if (LOGD) Log.d(TAG, "Multiple options, no default yet");
                    // the bestMatch is probably the ResolveActivity, meaning the
                    // user has not yet selected a default
                    // so: we'll keep the original intent for now
                    mHotseats[i] = intent;

                    // set the accessibility text to "Select shortcut"
                    mHotseatLabels[i] = getText(R.string.title_select_shortcut);
                } else {
                    // we have an app!
                    // now reconstruct the intent to launch it through the front
                    // door
                    ComponentName com = new ComponentName(
                        bestMatch.activityInfo.applicationInfo.packageName,
                        bestMatch.activityInfo.name);
                    mHotseats[i] = new Intent(Intent.ACTION_MAIN).setComponent(com);

                    // load the app label for accessibility
                    mHotseatLabels[i] = bestMatch.activityInfo.loadLabel(pm);
                }
            }

            if (LOGD) {
                Log.d(TAG, "loadHotseats: hotseat " + i 
                    + " final intent=[" 
                    + ((mHotseats[i] == null)
                        ? "null"
                        : mHotseats[i].toUri(Intent.URI_INTENT_SCHEME))
                    + "] label=[" + mHotseatLabels[i]
                    + "]"
                    );
            }
        }
    }

有点复杂，主要代码其实如下：

 PackageManager pm = getPackageManager();
ResolveInfo bestMatch = pm.resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY);
List<ResolveInfo> allMatches = pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);

这样就获取了。下面以一个简单的例子结束，获取在sd卡中安装的程序列表：

private void getSdcardApps(){
		mSdcardAppsList.clear();
		ActivityManager am = (ActivityManager)mLauncher.getSystemService(Activity.ACTIVITY_SERVICE);
		PackageManager pm =mLauncher.getPackageManager();  
		List<android.content.pm.ApplicationInfo> list = pm.getInstalledApplications(PackageManager.GET_UNINSTALLED_PACKAGES);
		for (android.content.pm.ApplicationInfo appInfo : list) {
				if((appInfo.flags & android.content.pm.ApplicationInfo.FLAG_EXTERNAL_STORAGE) != 0){
					for (ApplicationInfo applicationInfo : mAllAppsList) {
						if(appInfo.packageName.equals(applicationInfo.componentName.getPackageName())){
							mSdcardAppsList.add(applicationInfo);
							break;
						}
					}
				}
		}
		mAppsAdapter = new AppsAdapter(getContext(), mSdcardAppsList);
		mAppsAdapter.notifyDataSetChanged();
		mGrid.setAdapter(mAppsAdapter);
		text.setVisibility(View.VISIBLE);
		text.setBackgroundResource(R.drawable.tab_mmenu_b3_normal);
	}