首先一起看看下面这张图:
通过前面锁屏加载流程可以知道在KeyguardSecurityContainer中使用getSecurityView()根据不同的securityMode inflate出来,并添加到界面上的。
我们知道,Pattern锁所使用的layout是 R.layout.keyguard_pattern_view;
<com.android.keyguard.KeyguardPatternView ...>
...
<com.android.internal.widget.LockPatternView
android:id="@+id/lockPatternView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:layout_marginEnd="8dip"
android:layout_marginBottom="4dip"
android:layout_marginStart="8dip"
android:layout_gravity="center_horizontal"
android:gravity="center"
android:clipChildren="false"
android:clipToPadding="false" />
...
</FrameLayout>
</com.android.keyguard.KeyguardPatternView>
那么图案解锁的滑动事件处理,就是在LockPatternView,是一个系统公共控件,下面我们就分析一下这个view是如何处理触摸输入的:
frameworks/base/core/java/com/android/internal/widget/LockPatternView.java
@Override
public boolean onTouchEvent(MotionEvent event) {
if (!mInputEnabled || !isEnabled()) {
return false;
}
switch(event.getAction()) {
case MotionEvent.ACTION_DOWN:
handleActionDown(event);
return true;
case MotionEvent.ACTION_UP:
handleActionUp();
return true;
case MotionEvent.ACTION_MOVE:
handleActionMove(event);
return true;
case MotionEvent.ACTION_CANCEL:
if (mPatternInProgress) {
setPatternInProgress(false);
resetPattern();
notifyPatternCleared();
}
if (PROFILE_DRAWING) {
if (mDrawingProfilingStarted) {
Debug.stopMethodTracing();
mDrawingProfilingStarted = false;
}
}
return true;
}
return false;
}
几种事件类型:
事件 | 简介 |
---|---|
ACTION_DOWN | 手指初次触摸到屏幕时触发 |
ACTION_MOVE | 手指在屏幕上滑动时触发,会多次触发 |
ACTION_UP | 手指离开屏幕时触发 |
ACTION_CANCEL | 事件被上层拦截时触发 |
ACTION_OUTSIDE | 手指不在控件区域时触发 |
不同的MotionEvent对应几个不同的handle方法处理,代码行数太多,我们这里大致总结如下:
关于历史坐标
为了效率,Android系统在处理ACTION_MOVE事件时会将连续的几个多触点移动事件打包到一个MotionEvent对象中。我们可以通过getX(int)和getY(int)来获得最近发生的一个触摸点事件的坐标,然后使用getHistorical(int,int)和getHistorical(int,int)来获得时间稍早的触点事件的坐标,二者是发生时间先后的关系。所以,我们应该先处理通过getHistoricalXX相关函数获得的事件信息,然后在处理当前的事件信息。
for (int i = 0; i < historySize + 1; i++) {
final float x = i < historySize ? event.getHistoricalX(i) : event.getX();
final float y = i < historySize ? event.getHistoricalY(i) : event.getY();
...
}
src/com/android/keyguard/KeyguardPatternView.java
private class UnlockPatternListener implements LockPatternView.OnPatternListener {
...
@Override
public void onPatternDetected(final List<LockPatternView.Cell> pattern) {
if (DEBUG) Log.d(TAG, "onPatternDetected");
mKeyguardUpdateMonitor.setCredentialAttempted();
mLockPatternView.disableInput();
if (mPendingLockCheck != null) {
mPendingLockCheck.cancel(false);
}
final int userId = KeyguardUpdateMonitor.getCurrentUser();
if (pattern.size() < LockPatternUtils.MIN_PATTERN_REGISTER_FAIL) {
mLockPatternView.enableInput();
onPatternChecked(userId, false, 0, false /* not valid - too short */);
return;
}
if (LatencyTracker.isEnabled(mContext)) {
LatencyTracker.getInstance(mContext).onActionStart(ACTION_CHECK_CREDENTIAL);
LatencyTracker.getInstance(mContext).onActionStart(ACTION_CHECK_CREDENTIAL_UNLOCKED);
}
mPendingLockCheck = LockPatternChecker.checkCredential(
mLockPatternUtils,
LockscreenCredential.createPattern(pattern), // 这里跟进去,会发现将 pattern转化成了 byte[]
userId,
new LockPatternChecker.OnCheckCallback() {
@Override
public void onEarlyMatched() {
if (DEBUG) Log.d(TAG, "onEarlyMatched");
if (LatencyTracker.isEnabled(mContext)) {
LatencyTracker.getInstance(mContext).onActionEnd(
ACTION_CHECK_CREDENTIAL);
}
onPatternChecked(userId, true /* matched */, 0 /* timeoutMs */,
true /* isValidPattern */);
}
@Override
public void onChecked(boolean matched, int timeoutMs) {
if (DEBUG) Log.d(TAG, "onChecked matched:" + matched);
if (LatencyTracker.isEnabled(mContext)) {
LatencyTracker.getInstance(mContext).onActionEnd(
ACTION_CHECK_CREDENTIAL_UNLOCKED);
}
mLockPatternView.enableInput();
mPendingLockCheck = null;
if (!matched) {
onPatternChecked(userId, false /* matched */, timeoutMs,
true /* isValidPattern */);
}
}
@Override
public void onCancelled() {
if (DEBUG) Log.d(TAG, "onCancelled");
// We already got dismissed with the early matched callback, so we
// cancelled the check. However, we still need to note down the latency.
if (LatencyTracker.isEnabled(mContext)) {
LatencyTracker.getInstance(mContext).onActionEnd(
ACTION_CHECK_CREDENTIAL_UNLOCKED);
}
}
});
if (pattern.size() > MIN_PATTERN_BEFORE_POKE_WAKELOCK) {
mCallback.userActivity();
mCallback.onUserInput();
}
}
...
}
在绘制密码后手指抬起的时候,如果已存的有效点数达到4个及以上,就会使用LockPatternChecker.checkCredential 方法调用 task.execute() 启动一个AsyncTask, 并在doInBackground中调用LockPatternUtils.checkCredential 进行密码验证,此时pattern会被转化成字节形式(LockscreenCredential.createPattern(pattern) 这里跟进去,会发现将 pattern转化成了 byte[])
// LockPatternUtils.java
public static byte[] patternToByteArray(List<LockPatternView.Cell> pattern) {
if (pattern == null) {
return new byte[0];
}
final int patternSize = pattern.size();
byte[] res = new byte[patternSize];
for (int i = 0; i < patternSize; i++) {
LockPatternView.Cell cell = pattern.get(i);
res[i] = (byte) (cell.getRow() * 3 + cell.getColumn() + '1');
}
return res;
}
最终和密码锁PIN码锁一样,都是远程调用到LockSettingsService 的 checkCredential 接口进行验证。
Keyguard接收用户输入的密码会通过Binder到framework层的LockSettingsService,LockSettingsService经过一系列调用会通过getGateKeeperService获取GateKeeperService然后调用verifyChallenge方法将密码继续忘底层传递,framework的调用栈如下:
java.lang.Throwab
comandroid.locksettings.1locksettings.LockSettingsService. spBasedDoVerifyCredential(LockSettingsService. java:2724)COT3767075server.ocksettingsLockSettingsService.doVerifyCredentia1(LockSettingsSeryice.java:2020comandroservercom android.server.locksettings.LockSettingsService.doVerifyCredential(LockSettingsService. jaya:1999atcom android.server.locksettings.LockSettingsService. checkCredential(LockSettingsService. java:1972)com android.internal.widget.ILockSettings$Stub.onTransact(ILockSettings.java:542atatexecTransactInternal(Binder.java:1159)execTransact(Binder.java:1123)at
SyntheticPasswordllanager. unwrapPasswordBasedSyntheticPassword(SyntheticPasswordllanager. java: 1016
android.os.Binderandroid.os.Binder