Question

我想打印一个嵌套的HashMap：

HashMap<Integer,HashMap<Character,Integer>> map;

我搜索了很多，但我找不到打印Integer的方法，因为当我在它上面使用getValues（）时，它告诉我：“找不到符号”。（因为它是一个整数值）

这就是我试图做的事情：

public void print(){
   for(Map.Entry<Integer, HashMap<Character,Integer>> t :this.map.entrySet()){
     Integer key = t.getKey();
     for (Map.Entry<Character,Integer> e : this.map.getValue().entrySet())
       System.out.println("OuterKey:" + key + " InnerKey: " + e.getKey()+ " VALUE:" +e.getValue());
   }
}

我不能在我的第二个中使用getValue（），那么我还能使用什么呢？

提前致谢！祝你今天愉快。克里斯。

Answer 1

getValue()是Map.Entry的方法，而不是Map。

您应该在第二个循环中使用t.getValue().entrySet()而不是this.map.getValue().entrySet()。

那会给你内在的地图。

public void print(){
   for(Map.Entry<Integer, HashMap<Character,Integer>> t :this.map.entrySet()){
     Integer key = t.getKey();
     for (Map.Entry<Character,Integer> e : t.getValue().entrySet())
       System.out.println("OuterKey:" + key + " InnerKey: " + e.getKey()+ " VALUE:" +e.getValue());
   }
}

Answer 2

打印整件事的最简单方法：

System.out.println(map.toString());

是的，就是这样; toString（）返回一个字符串...，其中包含您Map的所有内容;包括其内部地图！

如果你想自己做，那么你可以使用两个循环：

for(Map.Entry<Integer, HashMap<Character,Integer>> innerMap : map.entrySet()) {
  for (Map.Entry<Character, Integer> aMap : innerMap.entrySet) {
    ... now you can call aMap.getKey() and .getValue()

Answer 3

#import "ViewController.h"

@interface ViewController ()
// Create IBOutlet for the progressView's width constraint
@property (nonatomic, weak) IBOutlet NSLayoutConstraint *progressViewWidthContraint;

// Declare a timer
@property (nonatomic, strong) NSTimer *progressTimer;
@property (nonatomic, assign) CGFloat progressPerSecond;

@end

@implementation ViewController 

// Progress time can be changed on demand
NSInteger kProgressTime = 60;

- (void)viewWillAppear:(BOOL)animated {
    [super viewWillAppear:animated];
// Lets setup how much should the progress be increased by a second
    self.progressPerSecond = self.view.frame.size.width / kProgressTime;
// Lets start showing the progress
    [self startOrResetTimer];
}

- (void)startOrResetTimer {
// Just in case invalidate the timer before we would set it up
    [self.progressTimer invalidate];
// Set the progressView's constant to its initial phase    
    self.progressViewWidthContraint.constant = 0;
    [self.view setNeedsLayout];
    [self.view layoutIfNeeded];
// Create the timer    
    self.progressTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(updateProgress) userInfo:nil repeats:true];
}

- (void)updateProgress {
    // If the progress has reached the end of the screen, do not increase the constraint's constant
    if (self.progressViewWidthContraint.constant == self.view.frame.size.width) {
        return;
    }

    // Increase the constant by the previously calculated progress per second
    self.progressViewWidthContraint.constant += self.progressPerSecond;
    [self.view setNeedsLayout];
    [self.view layoutIfNeeded];
}

// Hook this method to your reset button on the interface builder, and any time you press the button, it will reset the timer and the progressbar
- (IBAction)didTapResetTimerButton:(UIButton *)sender {
    [self startOrResetTimer];
}

@end

希望它有效。

如何使用Integer迭代和打印嵌套的HashMap作为值？

3 个答案: