解决当设置最大高度小于textView本身高度的时候不能滚动的问题

WZBbiao · Dec 28, 2016 · 3573ffc · 3573ffc
1 parent d0d599f
commit 3573ffc
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Showing 3 changed files with 53 additions and 12 deletions.
diff --git a/WZBTextView-demo.xcodeproj/project.pbxproj b/WZBTextView-demo.xcodeproj/project.pbxproj
@@ -528,6 +528,7 @@
 				986FE9C71DD9AB190091617F /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 		986FE9C81DD9AB190091617F /* Build configuration list for PBXNativeTarget "WZBTextView-demoTests" */ = {
 			isa = XCConfigurationList;
@@ -536,6 +537,7 @@
 				986FE9CA1DD9AB190091617F /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 		986FE9CB1DD9AB190091617F /* Build configuration list for PBXNativeTarget "WZBTextView-demoUITests" */ = {
 			isa = XCConfigurationList;
@@ -544,6 +546,7 @@
 				986FE9CD1DD9AB190091617F /* Release */,
 			);
 			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
 		};
 /* End XCConfigurationList section */
 	};

diff --git a/WZBTextView-demo/ViewController.m b/WZBTextView-demo/ViewController.m
@@ -12,14 +12,26 @@
 @interface ViewController () <UINavigationControllerDelegate, UIImagePickerControllerDelegate>
 @property (weak, nonatomic) IBOutlet UITextView *textView;
 @property (nonatomic, strong) UITextView *tView;
+
 @end
 
 @implementation ViewController
 
 - (void)viewDidLoad {
     [super viewDidLoad];
+
+    [self test1];
+}
+
+- (void)test1 {
+    self.textView.hidden = NO;
     self.textView.placeholder = @"i love you";
     self.textView.maxHeight = 100.05;
+}
+
+- (void)test2 {
+    self.textView.hidden = YES;
+
     UITextView *textView = [[UITextView alloc] initWithFrame:(CGRect){0, 0, 200, 30}];
     [self.view addSubview:textView];
     textView.center = self.view.center;
@@ -35,7 +47,7 @@ - (void)viewDidLoad {
         }];
     }];
     self.tView = textView;
-    UIButton *button = [[UIButton alloc] initWithFrame:(CGRect){20, 30, 50, 25}];
+    UIButton *button = [[UIButton alloc] initWithFrame:(CGRect){20, 30, 100, 25}];
     [self.view addSubview:button];
     [button setTitle:@"添加图片" forState:UIControlStateNormal];
     [button setTitleColor:[UIColor lightGrayColor] forState:UIControlStateNormal];

diff --git a/WZBTextView-demo/WZBTextView/UITextView+WZB.m b/WZBTextView-demo/WZBTextView/UITextView+WZB.m
@@ -25,27 +25,36 @@ @interface UITextView ()
 @implementation UITextView (WZB)
 
 - (UITextView *)placeholderView {
+
     // 为了让占位文字和textView的实际文字位置能够完全一致，这里用UITextView
     UITextView *placeholderView = objc_getAssociatedObject(self, WZBPlaceholderViewKey);
+
     if (!placeholderView) {
+
         placeholderView = [[UITextView alloc] init];
+
         // 动态添加属性的本质是: 让对象的某个属性与值产生关联
         objc_setAssociatedObject(self, WZBPlaceholderViewKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
         placeholderView = placeholderView;
+
         // 设置基本属性
         self.scrollEnabled = placeholderView.scrollEnabled = placeholderView.showsHorizontalScrollIndicator = placeholderView.showsVerticalScrollIndicator = placeholderView.userInteractionEnabled = NO;
         placeholderView.textColor = [UIColor lightGrayColor];
         placeholderView.backgroundColor = [UIColor clearColor];
         [self refreshPlaceholderView];
         [self addSubview:placeholderView];
+
         // 监听文字改变
         [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(textViewTextChange) name:UITextViewTextDidChangeNotification object:self];
+
         // 这些属性改变时，都要作出一定的改变，尽管已经监听了TextDidChange的通知，也要监听text属性，因为通知监听不到setText：
         NSArray *propertys = @[@"frame", @"bounds", @"font", @"text", @"textAlignment", @"textContainerInset"];
+
         // 监听属性
         for (NSString *property in propertys) {
             [self addObserver:self forKeyPath:property options:NSKeyValueObservingOptionNew context:nil];
         }
+
     }
     return placeholderView;
 }
@@ -80,28 +89,23 @@ - (void)setPlaceholder:(NSString *)placeholder
 
 - (NSString *)placeholder
 {
-    // 获取对应属性的值
-
-    UITextView *placeholderView = objc_getAssociatedObject(self, WZBPlaceholderViewKey);
-
     // 如果有placeholder值才去调用，这步很重要
-    if (placeholderView) {
+    if (self.placeholderExist) {
         return [self placeholderView].text;
     }
     return nil;
 }
 
 - (void)setPlaceholderColor:(UIColor *)placeholderColor
 {
-    // 动态添加属性的本质是: 让对象的某个属性与值产生关联
-    objc_setAssociatedObject(self, WZBPlaceholderColorKey, placeholderColor, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-    UITextView *placeholderView = objc_getAssociatedObject(self, WZBPlaceholderViewKey);
-
     // 如果有placeholder值才去调用，这步很重要
-    if (placeholderView) {
+    if (self.placeholderExist) {
         NSLog(@"请先设置placeholder值！");
     } else {
         self.placeholderView.textColor = placeholderColor;
+
+        // 动态添加属性的本质是: 让对象的某个属性与值产生关联
+        objc_setAssociatedObject(self, WZBPlaceholderColorKey, placeholderColor, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
     }
 }
 
@@ -110,7 +114,15 @@ - (UIColor *)placeholderColor {
 }
 
 - (void)setMaxHeight:(CGFloat)maxHeight {
-    objc_setAssociatedObject(self, WZBTextViewMaxHeightKey, [NSString stringWithFormat:@"%lf", maxHeight], OBJC_ASSOCIATION_COPY_NONATOMIC);
+
+    CGFloat max = maxHeight;
+
+    // 如果传入的最大高度小于textView本身的高度，则让最大高度等于本身高度
+    if (maxHeight < self.frame.size.height) {
+        max = self.frame.size.height;
+    }
+
+    objc_setAssociatedObject(self, WZBTextViewMaxHeightKey, [NSString stringWithFormat:@"%lf", max], OBJC_ASSOCIATION_COPY_NONATOMIC);
 }
 
 - (CGFloat)maxHeight {
@@ -160,6 +172,20 @@ - (void)autoHeightWithMaxHeight:(CGFloat)maxHeight textViewHeightDidChanged:(voi
     self.textViewHeightDidChanged = textViewHeightDidChanged;
 }
 
+// 判断是否有placeholder值，这步很重要
+- (BOOL)placeholderExist {
+
+    // 获取对应属性的值
+    UITextView *placeholderView = objc_getAssociatedObject(self, WZBPlaceholderViewKey);
+
+    // 如果有placeholder值
+    if (placeholderView) {
+        return YES;
+    }
+
+    return NO;
+}
+
 - (void)addImage:(UIImage *)image {
     [self addImage:image size:CGSizeZero];
 }