Android 蓝牙配对PIN码错误

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信息小飞侠 2024-10-21 23:17:52

文章标签 Android 蓝牙配对PIN码错误 android java sed 文章分类 Android 移动开发

背景描述

客户反馈售后问题，设置pin码解锁后，锁屏解锁，输入1234，界面显示4**4，能正常解锁。

问题分析

分析pin码解锁界面点击事件和密码框显示逻辑：
pin码显示界面键盘和密码框为自定义view，非系统软键盘和基础控件EditText。
界面中点击事件下发、密码框显示数字、数字过几秒变为*等逻辑，均为自定义控件内部逻辑。
关键类：

SystemUI/src/com/android/keyguard/PasswordTextView.java
SystemUI/src/com/android/keyguard/NumPadKey.java

PasswordTextView

SystemUI/src/com/android/keyguard/PasswordTextView.java中

//用户点击数字的对象列表，每一个显示的数字都是一个CharState，CharState负责记录点击的值和从数字变为*的动画
private ArrayList<CharState> mTextChars = new ArrayList<>();
//密码拼接字符串，用来解锁时验证密码是否和设置的pin码匹配
private String mText = "";
//栈，用来缓存CharState对象，在用户频繁输入删除时，防止每次点击都new对象
private Stack<CharState> mCharPool = new Stack<>();

密码显示的绘制

protected void onDraw(Canvas canvas) {
...
int length = mTextChars.size();
for (int i = 0; i < length; i++) {
    CharState charState = mTextChars.get(i);
    float charWidth = charState.draw(canvas, currentDrawPosition, charHeight, yPosition, 
    charLength);
    currentDrawPosition += charWidth;
}
...
}

charState.draw里面绘制具体的数字或者·

public float draw(Canvas canvas, float currentDrawPosition, int charHeight, float yPosition,
        float charLength) {
    boolean textVisible = currentTextSizeFactor > 0;
    boolean dotVisible = currentDotSizeFactor > 0;
    float charWidth = charLength * currentWidthFactor;
    if (textVisible) {//绘制数字
        float currYPosition = yPosition + charHeight / 2.0f * currentTextSizeFactor
                + charHeight * currentTextTranslationY * 0.8f;
        canvas.save();
        float centerX = currentDrawPosition + charWidth / 2;
        canvas.translate(centerX, currYPosition);
        canvas.scale(currentTextSizeFactor, currentTextSizeFactor);
        canvas.drawText(Character.toString(whichChar), 0, 0, mDrawPaint);
        canvas.restore();
    }
    if (dotVisible) {//绘制·
        canvas.save();
        float centerX = currentDrawPosition + charWidth / 2;
        canvas.translate(centerX, yPosition);
        canvas.drawCircle(0, 0, mDotSize / 2 * currentDotSizeFactor, mDrawPaint);
        canvas.restore();
    }
    return charWidth + mCharPadding * currentWidthFactor;
}

点击事件
NumPadKey是0-9的数字，点击事件调用PasswordTextView的append方法
NumPadKey中：

if (mTextView != null && mTextView.isEnabled()) {
    mTextView.append(Character.forDigit(mDigit, 10));
}

PasswordTextView中：

public void append(char c) {
    int visibleChars = mTextChars.size();
    CharSequence textbefore = getTransformedText();
    mText = mText + c;//字串拼接
    int newLength = mText.length();
    CharState charState;
    if (newLength > visibleChars) {
        charState = obtainCharState(c);//获取CharState对象
        mTextChars.add(charState);//添加到列表中
    } else {
        charState = mTextChars.get(newLength - 1);
        charState.whichChar = c;
    }
    charState.startAppearAnimation();
    ...
}
//mCharPool维护一个栈，防止输入删除频繁创建对象
    private CharState obtainCharState(char c) {
        CharState charState;
        if(mCharPool.isEmpty()) {
            charState = new CharState();
        } else {
            charState = mCharPool.pop();
            charState.reset();
        }
        charState.whichChar = c;
        return charState;
    }

Log分析

在流程中添加log，打印onDraw方法和append方法和obtainCharState方法
1、onDraw方法中log

01-05 12:04:52.780009  1823  1823 W xiaohe  : onDraw 333 mText: 12 mTextCharTmp: 12
01-05 12:04:52.841712  1823  1823 W xiaohe  : onDraw 333 mText: 123 mTextCharTmp: 323

mText和mTextChar的值不一致。
点击1、2、3，12的时候还是一致的，当点击3的时候显示为3*3
2、append方法中的log

01-05 12:04:52.834189  1823  1823 D xiaohe  : PasswordTextview append display:[CharState{whichChar=3,textAnimationIsGrowing=false,dotAnimationIsGrowing=true,currentTextSizeFactor=0.0}, CharState{whichChar=2,textAnimationIsGrowing=true,dotAnimationIsGrowing=false,currentTextSizeFactor=1.0}, CharState{whichChar=3,textAnimationIsGrowing=false,dotAnimationIsGrowing=true,currentTextSizeFactor=0.0}] password:123

注意列表中第一个CharState不仅字符值被改了，动画进度和标志位也被重置。
mTextChar列表中第一个和第三个对象值完全一样，怀疑它们是同一个对象。

方案

append方法中添加去重判断，CharState toString打印hashcode值。

public void append(char c) {
    int visibleChars = mTextChars.size();
    CharSequence textbefore = getTransformedText();
    mText = mText + c;//字串拼接
    int newLength = mText.length();
    CharState charState;
    if (newLength > visibleChars) {
		while(mTextChars.contains(charState)){//去重
		    android.util.Log.e("xiaohe","PasswordTextview append contains=== ");
		    charState = obtainCharState(c);
		}
		charState.reset();//从obtainCharState中移出来,确认不重复再重置状态赋值
		charState.whichChar = c;//从obtainCharState中移出来,确认不重复再重置状态赋值
		mTextChars.add(charState);
    }
...
}

修改后问题压测不复现

复测Log分析

//第一次点击
//mCharPool栈信息
01-06 11:54:16.592287  1907  1907 D xiaohe  : obtainCharState === mCharPool: [CharState{whichChar=0,HashCode=5aba0d}, CharState{whichChar=0,HashCode=8e2cc34}, CharState{whichChar=0,HashCode=b1ecc7e}, CharState{whichChar=1,HashCode=44fe8e}, CharState{whichChar=0,HashCode=3342ac4}, CharState{whichChar=0,HashCode=3342ac4}]
//从obtainCharState中pop出一个对象
01-06 11:54:16.592395  1907  1907 D xiaohe  : =====PasswordTextview append charState:CharState{whichChar=0,HashCode=3342ac4}
//打印列表mTextChars列表
01-06 11:54:16.592408  1907  1907 D xiaohe  : =====PasswordTextview append mTextChars:[]
//列表为空，中没有包含3342ac4对象
//将要添加到列表中的对象确定为3342ac4
01-06 11:54:16.592483  1907  1907 W xiaohe  : +++++PasswordTextview append charState:CharState{whichChar=1,HashCode=3342ac4}
//添加完之后的列表
01-06 11:54:16.592523  1907  1907 W xiaohe  : +++++PasswordTextview append mTextChars:[CharState{whichChar=1,HashCode=3342ac4}]
01-06 11:54:16.592538  1907  1907 W xiaohe  : PasswordTextview append display:[CharState{whichChar=1,HashCode=3342ac4}] password:1
//第二次点击
//mCharPool栈信息
01-06 11:54:16.791004  1907  1907 D xiaohe  : obtainCharState === mCharPool: [CharState{whichChar=0,HashCode=5aba0d}, CharState{whichChar=0,HashCode=8e2cc34}, CharState{whichChar=0,HashCode=b1ecc7e}, CharState{whichChar=1,HashCode=44fe8e}, CharState{whichChar=1,HashCode=3342ac4}]
//从obtainCharState中pop出一个对象
01-06 11:54:16.791055  1907  1907 D xiaohe  : =====PasswordTextview append charState:CharState{whichChar=1,HashCode=3342ac4}
//打印列表mTextChars列表
01-06 11:54:16.791067  1907  1907 D xiaohe  : =====PasswordTextview append mTextChars:[CharState{whichChar=1,HashCode=3342ac4}]
//新增检测机制，判断3342ac4已经存在列表中
01-06 11:54:16.791092  1907  1907 E xiaohe  : PasswordTextview append contains===
//mCharPool栈信息
01-06 11:54:16.791120  1907  1907 D xiaohe  : obtainCharState === mCharPool: [CharState{whichChar=0,HashCode=5aba0d}, CharState{whichChar=0,HashCode=8e2cc34}, CharState{whichChar=0,HashCode=b1ecc7e}, CharState{whichChar=1,HashCode=44fe8e}]
//再次从obtainCharState中pop出一个对象
//列表中不包含新的对象44fe8e
01-06 11:54:16.791169  1907  1907 W xiaohe  : +++++PasswordTextview append charState:CharState{whichChar=2,HashCode=44fe8e}
//添加完之后的列表
01-06 11:54:16.791181  1907  1907 W xiaohe  : +++++PasswordTextview append mTextChars:[CharState{whichChar=1,HashCode=3342ac4}, CharState{whichChar=2,HashCode=44fe8e}]
01-06 11:54:16.791196  1907  1907 W xiaohe  : PasswordTextview append display:[CharState{whichChar=1,HashCode=3342ac4}, CharState{whichChar=2,HashCode=44fe8e}] password:12

第一次点击，mCharPool栈里面pop出一个对象3342ac4，添加到append display列表中
第二次点击，mCharPool再次pop出一个对象3342ac4，试图添加到列表中，把对象改为2时。因为和第一个对象是同一个对象，对象的值和动画进度都被重置到初始状态，即显示22.
在这里添加判断，判断到列表中已经有该对象，不进行添加，再次pop出下一个元素44fe8e用来记录第二次的点击值。

为什么mCharPool里的值会重复

在mCharPool.push的地方添加堆栈打印log。
1、点击删除按钮，做移除动画，动画结束时

@Override
public void onAnimationEnd(Animator animation) {
    if (!mCancelled) {
        mTextChars.remove(CharState.this);//动画结束，从列表删除对象
        mCharPool.push(charState);//动画结束，把对象添加到栈
        reset();
        cancelAnimator(textTranslateAnimator);
        textTranslateAnimator = null;
    }
}

01-08 15:01:55.088606  1823  1823 D xiaohe  : reset startRemoveAnimation dotNeedsAnimation: true textNeedsAnimation: false widthNeedsAnimation: true ---- java.lang.Throwable
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at com.android.keyguard.PasswordTextView$CharState.startRemoveAnimation(PasswordTextView.java:677)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at com.android.keyguard.PasswordTextView.deleteLastChar(PasswordTextView.java:361)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at com.android.keyguard.KeyguardPinBasedInputViewController.lambda$onViewAttached$3(KeyguardPinBasedInputViewController.java:90)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at com.android.keyguard.KeyguardPinBasedInputViewController.$r8$lambda$sVhaIBw-pegVYYoUq1EphloEbjc(Unknown Source:0)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at com.android.keyguard.KeyguardPinBasedInputViewController$$ExternalSyntheticLambda0.onClick(Unknown Source:2)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at android.view.View.performClick(View.java:7455)
01-08 15:01:55.088606  1823  1823 D xiaohe  : 	at android.view.View.performClickInternal(View.java:7428)

2、KeyguardAbsKeyInputViewController.onPause，调用reset直接push了对象。

01-08 15:01:55.134947  1823  1823 D xiaohe  : reset animated: false announce: false length: 1
01-08 15:01:55.135042  1823  1823 D xiaohe  : reset mCharPool.push(charState): CharState{whichChar=1,HashCode=93c0038}
01-08 15:01:55.135716  1823  1823 I xiaohe  :  ---- java.lang.Throwable
01-08 15:01:55.135716  1823  1823 I xiaohe  : 	at com.android.keyguard.PasswordTextView.reset(PasswordTextView.java:452)
01-08 15:01:55.135716  1823  1823 I xiaohe  : 	at com.android.keyguard.KeyguardPinBasedInputView.resetPasswordText(KeyguardPinBasedInputView.java:148)
01-08 15:01:55.135716  1823  1823 I xiaohe  : 	at com.android.keyguard.KeyguardAbsKeyInputViewController.reset(KeyguardAbsKeyInputViewController.java:142)
01-08 15:01:55.135716  1823  1823 I xiaohe  : 	at com.android.keyguard.KeyguardAbsKeyInputViewController.onPause(KeyguardAbsKeyInputViewController.java:394)
01-08 15:01:55.135716  1823  1823 I xiaohe  : 	at com.android.keyguard.KeyguardPinViewController.onPause(KeyguardPinViewController.java:166)

2者同时操作了同一个对象，导致push重复。